Nonsense! Until the dawn of modern communication, certain knowledge of the name of a reigning Roman Pontiff rarely existed beyond the duchies and city-states of Italy as well as regal capitals and primatial sees of western Europe. Most bishops and priests would mention the name of the last pope whom they had been told is reigning who was often already dead and succeeded. The operative principle is union with the Office of Peter, then union with the occupant of that office insofar as that can be known.

You, living in this age of instant communication, are not excused. The fake Pope says that "he likes to believe Hell is empty."  Jesus himself said (Matthew 7:13-14):

 13 Enter ye in at the narrow gate: for wide is the gate, and broad is the way that leadeth to destruction, and many there are who go in thereat.
Intrate per angustam portam : quia lata porta, et spatiosa via est, quae ducit ad perditionem, et multi sunt qui intrant per eam.

 14 How narrow is the gate, and strait is the way that leadeth to life: and few there are that find it!
Quam angusta porta, et arcta via est, quae ducit ad vitam : et pauci sunt qui inveniunt eam!

To not care that the guy who contradicts Jesus claims to be the Pope is a scandal.

If Fr. Epiney and Bishop Roy are telling the truth, that means that any priest or Bishop of the SSPX or the Marian Corps (Resistance) should be free to make the decision on "una cuм" according to his conscience and his knowledge of the Crisis.  He should certainly not be expelled from the Society or the Resistance for following their Founder's example!!

Fr. Epiney and Bishop Roy are *not* telling the truth. Personally I believe they are repeating a lie they think is the truth. IMO, the reason they think it's the truth is because they think nothing of omitting the name of the pope in the Canon of the Mass themselves and have convinced themselves it is actually a sin to do so.

+ABL certainly understood that per Quo Primum and since Quo Primum, no priest (or bishop or pope) is free to choose which parts of the Roman Liturgy he wants to add or omit in the Canon of the Mass.

Priests, because they have knowledge of the crisis does not mean their knowledge qualifies them to choose to omit the name of the pope in the canon of the Mass, because the Church teaches that to do so is an act of schism, it is at the very least certainly breaking the Church's Law on the Roman Liturgy. But what they do not grasp is that the Mass not theirs and they are not permitted to change one word of it - period, lex orandi lex credendi.

+ABL knew he had no right to change a word of it and never did - they don't/can't/won't grasp this. I think by omitting the name of the pope, they changed their lex orandi, which gives them the lex credendi they have now.

Fr. Epiney and Bishop Roy are *not* telling the truth. Personally I believe they are repeating a lie they think is the truth.

You believe what you want to believe.  Father Epiney seems reliable, and I don't have any reason to believe that Bishop Roy would lie either.  And, given that it's not all that complicated a matter, I don't believe that this was an instance of "telephone game" either.

If a sede priest says mass una cuм, it’s not a mortal sin.  And vice versa.  The whole debate over this prayer is the dumbest, most fabricated, most outlandish nonsense I’ve ever heard.  

Fr. Epiney and Bishop Roy are *not* telling the truth. Personally I believe they are repeating a lie they think is the truth. IMO, the reason they think it's the truth is because they think nothing of omitting the name of the pope in the Canon of the Mass themselves and have convinced themselves it is actually a sin to do so.

+ABL certainly understood that per Quo Primum and since Quo Primum, no priest (or bishop or pope) is free to choose which parts of the Roman Liturgy he wants to add or omit in the Canon of the Mass.

Priests, because they have knowledge of the crisis does not mean their knowledge qualifies them to choose to omit the name of the pope in the canon of the Mass, because the Church teaches that to do so is an act of schism, it is at the very least certainly breaking the Church's Law on the Roman Liturgy. But what they do not grasp is that the Mass not theirs and they are not permitted to change one word of it - period, lex orandi lex credendi.

+ABL knew he had no right to change a word of it and never did - they don't/can't/won't grasp this. I think by omitting the name of the pope, they changed their lex orandi, which gives them the lex credendi they have now.

Dear Stubborn,

The names of a pope or a bishop in the Canon of the Mass are just like the feast days of saints; movable (people die, some become new saints).
Canon XIII of the Seventh Session does not preclude the changes in the liturgy outside of the rites of the sacraments. One does not incur anathema by not putting the name of the pope or the bishop into the provided space. These men even in regular times can be out of Office ( the state of sedevacante). One does, however, incur anathema by putting the name of St. Joseph to an unchangeable Canon of the Mass. Pope John XXIII is under anathema of Trent and the wrath of Sts. Peter and Paul of Quo Primum.

This is the problem with the 1962 Missal, and Father Ratzinger knew this. That is why he was not only OK with the 1962 liturgy, but in "Summorum Pontificuм" he made sure that the Mass of Pope St. Pius V does not return.
Abp. Lefebvre imposed the 1962 liturgy on the SSPX. Did he ever say the new Mass? Did he "ordain" (God forbid!) a priest with a new rite of Order?

By the way, your statement that Fr. Pierre Epiney, who is the primary source of information, is "repeating a lie" is a defamation of a very holy priest, unless you have specific proof to the contrary. Bishop Pierre Roy, ordained by Bp. Williamson and consecrated by Bp. de Silva, who was ordained to the Priesthood by Bishop Williamson in 2017, is a valid Roman Catholic Bishop. We owe him at least the benefit of the doubt that he would not disseminate disinformation.

Casting doubts on the name, character, and reputation of true priests and bishops carries a heavy burden of proof for a lay Catholic.

If a sede priest says mass una cuм, it’s not a mortal sin.  And vice versa.  The whole debate over this prayer is the dumbest, most fabricated, most outlandish nonsense I’ve ever heard. 

This isn't about whether it's sinful.  There are a handful of dogmatic non-una-cuм types out there, but most are not.  What's under discussion is the implication that +Lefebvre may have gone sedevacantist before he died.

One does, however, incur anathema by putting the name of St. Joseph to an unchangeable Canon of the Mass. Pope John XXIII is under anathema of Trent and the wrath of Sts. Peter and Paul of Quo Primum.

You don't know what you're talking about.  The original edition of the 62 missal, the one approved directly by J23 does NOT have the addition of St Joseph.  It was after this missal was approved, that the liturgy was handed off to a commission/committee, and then from 62 to 65, there were constant and repeated updates to the missal, until the 65 missal came out, which was then revised very soon after that. 

This is the problem with the 1962 Missal

There is nothing wrong with the 62 missal, original edition.  Most clerics knew the addition of St Joseph was done by a committee vs the pope, which is why they had no problems ignoring the St Joseph change.

Casting doubts on the name, character, and reputation of true priests and bishops carries a heavy burden of proof for a lay Catholic.

No, the burden of proof is on these clerics for making such a statement, nearly 30 years after +ABL is dead.