I had a discussion with a Novus Ordo FOCUS missionary at the college I go to. I am currently involved in a Bible study with him and another student, since I thought it would be a good way to make friends on a "Catholic" college campus. Feels pretty lonely since it basically functions like a worldly public university, but has some Catholic imagery here and there, and even a beautiful small chapel. Prior to this meeting, I had sent him several videos on Quo Primum to look at in his free time, since the topic of the traditional latin mass came up in our previous discussion. 
I explained to him in the most charitable way possible that I was not okay with going to the Novus Ordo Mass, using Quo Primum and Auctorem Fidei to back up my argument, as well as bringing up what the late Fr. Hesse had to say about these docuмents. Like Fr. Hesse, I take the position that the NO mass is probably valid but illicit. 

Today he invited me to meet with him, and we continued our discussion on the NO. He told me that he had watched some of the videos that I had sent him, and had even ended up researching the SSPX position on the issue. Thankfully, he did not repeat the absurd claim that the Society is in schism with Rome. The conversation inevitably veered into Church Authority, and this where things got a little more tense. He ended up saying that if the modern Church approves of the NO, then he has no reason to question it. I found this perplexing, and brought up many of the problems of the JPII papacy and the current Francis pontificate to try to get him to realize that he cannot trust these churchmen. Sadly, it didn't seem to have an effect on him. For example, I pointed out the incident where JPII kissed the Koran. He claimed that maybe JPII didn't mean to show that he approved of Islam, and that could mean something different to Middle Easterners. I replied by saying that even if that were true, JPII must have known that this would scandalize the millions of Catholics in the West. He then said that we can't judge the pope's intentions, and even quoted PF by saying "Who am I to judge?". There were several more problematic things I brought up (PF pulling the ring away, Assisi prayer meeting, etc.) but he basically gave the same response for each one. Canonizations also briefly came up, when I was asked if JPII is a saint. I said that if the Church said that he's in heaven, then he probably is there. I also added that I had doubts about his canonization, since he committed many publicly, and was cut off with the accusation that I "think that I know better than the Church". I've read up on the issue of Newchurch canonizations, but would definitely appreciate more clarity on the issue.    

I pointed out that we can judge the actions of the pope, and should not follow him into error/heresy, and that there have been heretical popes before. He agreed with this, but strangely said that he would rather follow PF, since he could not believe that God could put us in a position where we don't have to listen to the modern church hierarchy. He also added that I should not listen to Fr. Hesse/Archbishop Lefebvre, since they may not have had a "proper interpretation" of Church Tradition, and that we should instead listen to the modern Magisterium, and the pope. I was unsure of how to address the modern Magisterium, since it's a topic I haven't looked into that much. But, I basically gave the reply that we cannot trust the Magisterium if it is made up of modernists. I would like more info on the Magisterium, links would be very much appreciated. 

He also claimed that Quo Primum did not bind future popes, which is false, but I didn't know how to refute him there. I had sent him the papalencylicals.net version of Quo Primum, so maybe there is something wrong with that translation. The discussion ended on decent terms, but I could not help but feel legitimately angry during and after this conversation due to hearing such blatant nonsense. Throughout the conversation I made sure to ask the Lord to give me charity, since I didn't want this to turn into a shouting match. Some additional info: this missionary was educated at Steubenville, and told me that he had studied modernism/papal docuмents. He is also a believer in Medjugorje, and claims that 10 of those "apparitions" have been approved. 

With all of this said, I pray that this man can see through the lies and accept the truth. 
I ask for all of your advice on what to do with this issue, and request your prayers as well. I'll pray for all of you too. 

As far as Quo Primum (QP) goes, he’s right (in theory) that it cannot bind future popes.  He’s wrong (in practice) because QP was never abrogated (overruled or nullified), therefore it DOES bind all current popes.  
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All one has to do is read Benedict’s motu of 2007, and he plainly says that the 1962 missal was never abrogated.  This proves that QP isn’t abrogated either, because the 62 missal IS THE MISSAL of QP.  You can’t have the 62 missal without QP and vice versa.
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Since QP is law, then the follow is true:
1.  The old rite is legal, moral and is allowable to be used by any priest, at all times, forever.  (This permission obviously extends to the laity too).
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2.  QP does not allow ANY OTHER rite to be used in the Latin Church.  It allows no edits, additions or deletions to the rite.  This under pain of sin.  Ergo, the novus ordo is illegal because Benedict’s “motu” explanation that the novus ordo isn’t a new rite but a “different usage” of the same rite.  QP only allows one usage, so a different one is illegal and sinful. 
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3.  Often overlooked in QP is the COMMAND that ONLY this rite be used, and none other.  This is ordered under obedience to the papacy.  Ergo, those of the Latin Church that do not use this rite commit a grave sin.
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4.  Nowhere, anywhere, in any capacity, does Paul VI’s law command any catholic to use, accept or attend a new mass.  All Paul VI did, legally, was create a new missal.  It’s not obligatory in any degree, as far as new-Rome is concerned.  Now, all the diocesan bishops/priests will tell you that you have to go, but they are also the ones who said that QP and the True Mass were outlawed, so their opinion, on legal matters, is sketchy and untrustworthy.  Benedict’s “motu” is a clear legal answer to all of Traditionalism’s questions and is a total legal and moral vindication of the anti-V2 movement.  Of all the bad things that Benedict did as a clergyman, in this, he did a great thing. 

Thanks! Could you provide me a link for Paul VI saying that the NO was not obligatory? Some hard evidence/quotes would be really helpful. 

No, I don't have anything like that.  You have to read between the lines, as the Modernists have only admitted this fact indirectly.
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If you read Paul VI's apostolic constitution where he created the new missal, nowhere does he say who has to attend it, when this obligation starts, and there is no penalty for not attending it.  If you contrast that to all previous liturgical laws related to missal editions, especially St Pius V's law of QP, the differences are stark.  In order for a law to be obligatory, it must be clear to whom it applies, and how.  Below is a summary of a comparison between QP and Paul VI's law.
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Quo Primum from Pope St Pius V:
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Here is the example of legal language used by Pope St Pius V, when he enacted his law and revoked the previous liturgical missals:
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(1) Authorizing the new missal
Now therefore, in order that all everywhere may adopt and observe what has been delivered to them by the Holy Roman Church, Mother and Mistress of the other churches, it shall be unlawful henceforth and forever throughout the Christian world to sing or to read Masses according to any formula other than that of this Missal published by Us;

(2) who does this law apply to?
this ordinance to apply to all churches and chapels, with or without care of souls, patriarchal, collegiate, and parochial, be they secular or belonging to any religious Order, whether of men (including the military Orders) or of women, in which conventual Masses are or ought to be sung aloud in choir or read privately according to the rites and customs of the Roman Church; to apply, moreover, even if the said churches have been in any way exempted, whether by indult of the Apostolic See, by custom, by privilege, or even by oath or Apostolic confirmation, or have their rights and faculties guaranteed to them in any other way whatsoever

(3) What are the specifics of use & Penalties?
We specifically command each and every patriarch, administrator and all other persons of whatsoever ecclesiastical dignity, be they even Cardinals of the Holy Roman Church or possessed of any other rank or preeminence, and We order them by virtue of holy obedience to sing or to read the Mass according to the rite and manner and norm herein laid down by Us,

(4) Revoking of previous missals
and henceforward to discontinue and utterly discard all other rubrics and rites of other missals, howsoever ancient, which they have been accustomed to follow, and not to presume in celebrating Mass to introduce any ceremonies or recite any prayers other than those contained in this Missal.   (new mass)

(5) How long is this law in effect?
Furthermore, by these presents and by virtue of Our Apostolic authority We give and grant in perpetuity

(6) Permissions of this law?
that for the singing or reading of Mass in any church whatsoever, this Missal may be followed absolutely, without any scruple of conscience or fear of incurring any penalty, judgment or censure, and may be freely and lawfully used.

Nor shall bishops, administrators, canons, chaplains, and other secular priests, or religious of whatsoever Order or by whatsoever title designated, be obliged to celebrate Mass otherwise than enjoined by Us.  (new mass)

We likewise order and declare that no one whosoever shall be forced or coerced into altering this Missal  (new mass)

(7) Authority of this law?
and that this present Constitution can never be revoked or modified, but shall for ever remain valid and have the force of law

http://www.newadvent.org/library/docs_pi05qp.htm

Paul VI's Constitution:
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(1) Authorizing the new missal
...there has grown and spread among the Christian people the liturgical renewal which, according to Pius XII, Our predecessor of venerable memory, seems to show the signs of God's providence in the present time, a salvific action of the Holy Spirit in His Church.(2) This renewal has also shown clearly that the formulas of the Roman Missal ought to be revised and enriched.
Comment:  The new missal is authorized based on the 'liturgical renewal' which was started under Pius XII.  So, not authorized by Papal Authority, but by the authority of a dead pope.  Ok.  Makes total sense (sarcasm alert).
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The recent Second Vatican Ecuмenical Council, in promulgating the Constitution Sacrosanctum Concilium, established the basis for the general revision of the Roman Missal:
Comment:  The new missal is not authorized by papal authority.  Instead, V2 established "the basis" (i.e. argument) why the missal needed updating.  Still not any kind of authority is named which creates this missal, but only "the basis" for it being V2.  So not authorized by papal authority in any way.
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(2) who does this law apply to?
Not mentioned.
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(3) What are the specifics of use & Penalties?
We order that the prescriptions of this Constitution go into effect November 30th of this year, the first Sunday of Advent.
Comment:  The only prescriptions are related to the new missal's contents and layout.  There are no rules governing its use.
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(4) Revoking of previous missals
Not mentioned.
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(5) How long is this law in effect?
Not mentioned.
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(6) Permissions of this law?
Not mentioned.
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(7) Authority of this law?
In conclusion, we wish to give the force of law to all that we have set forth concerning the new Roman Missal.
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Comment:  You can see that all that is authorized by Paul VI is a new missal.  His only reason for producing a new missal is because Pope Pius XII started a liturgical renewal and V2 gives a "basis" for why a new missal would be a good idea.  The new missal applies to no one, there is no allowance to use it, nor penalities for not using it.  The new law mentions nothing about Quo Primum being changed or replaced.

Over half of the entire docuмent explains the changes of the new missal, which Quo Primum didn't even address.  If you cut out the detailed summary of Paul's new missal, his law would be a few sentences long.
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The Roman Missal, promulgated in 1570 by Our predecessor, St. Pius V, by decree of the Council of Trent,(1) has been received by all as one of the numerous and admirable fruits which the holy Council has spread throughout the entire Church of Christ. For four centuries, not only has it furnished the priests of the Latin Rite with the norms for the celebration of the Eucharistic Sacrifice, but also the saintly heralds of the Gospel have carried it almost to the entire world. Furthermore, innumerable holy men have abundantly nourished their piety towards God by its readings from Sacred Scripture or by its prayers, whose general arrangement goes back, in essence, to St. Gregory the Great.
(history lesson; no law present)
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 Since that time there has grown and spread among the Christian people the liturgical renewal which, according to Pius XII, Our predecessor of venerable memory, seems to show the signs of God's providence in the present time, a salvific action of the Holy Spirit in His Church.(2) This renewal has also shown clearly that the formulas of the Roman Missal ought to be revised and enriched. The beginning of this renewal was the work of Our predecessor, this same Pius XII, in the restoration of the Paschal Vigil and of the Holy Week Rite,(3) which formed the first stage of updating the Roman Missal for the present-day mentality.
(reasons for the new missal; no law present)
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 The recent Second Vatican Ecuмenical Council, in promulgating the Constitution Sacrosanctum Concilium, established the basis for the general revision of the Roman Missal: in declaring "both texts and rites should be drawn up so that they express more clearly the holy things which they signify";(4) in ordering that "the rite of the Mass is to be revised in such a way that the intrinsic nature and purpose of its several parts, as also the connection between them, can be more clearly manifested, and that devout and active participation by the faithful can be more easily accomplished";(5) in prescribing that "the treasures of the Bible are to be opened up more lavishly, so that richer fare may be provided for the faithful at the table of God's Word";(6) in ordering, finally, that "a new rite for concelebration is to be drawn up and incorporated into the Pontifical and into the Roman Missal."(7)
(reasons for the new missal from V2; no law present)
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 One ought not to think, however, that this revision of the Roman Missal has been improvident. The progress that the liturgical sciences has accomplished in the last four centuries has, without a doubt, prepared the way. After the Council of Trent, the study "of ancient manuscripts of the Vatican library and of others gathered elsewhere," as Our predecessor, St. Pius V, indicates in the Apostolic Constitution Quo primum, has greatly helped for the revision of the Roman Missal. Since then, however, more ancient liturgical sources have been discovered and published and at the same time liturgical formulas of the Oriental Church have become better known. Many wish that the riches, both doctrinal and spiritual, might not be hidden in the darkness of the libraries, but on the contrary might be brought into the light to illumine and nourish the spirits and souls of Christians.
(more reasons for the new missal; no law present)
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Let us show now, in broad lines, the new composition of the Roman Missal....
(here are the changes of the new missal, blah, blah, blah)
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In conclusion, we wish to give the force of law to all that we have set forth concerning the new Roman Missal. In promulgating the official edition of the Roman Missal, Our predecessor, St. Pius V, presented it as an instrument of liturgical unity and as a witness to the purity of the worship the Church. While leaving room in the new Missal, according to the order of the Second Vatican Council, "for legitimate variations and adaptations,"(15) we hope nevertheless that the Missal will be received by the faithful as an instrument which bears witness to and which affirms the common unity of all. Thus, in the great diversity of languages, one unique prayer will rise as an acceptable offering to our Father in heaven, through our High-Priest Jesus Christ, in the Holy Spirit.
This law created a new missal, nothing else.
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We order that the prescriptions of this Constitution go into effect November 30th of this year, the first Sunday of Advent.
This constitution orders a new missal, that's it.  There are no other prescriptions/commands of this law.  
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We wish that these Our decrees and prescriptions may be firm and effective now and in the future, notwithstanding, to the extent necessary, the apostolic constitutions and ordinances issued by Our predecessors, and other prescriptions, even those deserving particular mention and derogation.
This is legal wording that is at the end of 99% of legal, church docuмents.  What is given the "force of law"?  The creation of the missal and that's it.
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http://w2.vatican.va/content/paul-vi/en/apost_constitutions/docuмents/hf_p-vi_apc_19690403_missale-romanum.html

Thanks so much for the sources and commentary PV! This is very helpful, and just what I needed.