.
Typo --- Buenos Aires (you have Buenas Aires in thread title)
.
Maybe you got mixed up between buenos dias and buenas noches, but it's ALWAYS Buenos Aires.
.
Notice in the video, the Newpriest was told someone had dropped a host "in the back of the church." 
Then they show a picture of the priest looking at a host lying on the floor near the Communion rail.
.
Three problems with that:
1 --  The Communion rail had probably been removed from the church after the reforms of Vat.II
2 --  The host would not be near the Communion rail if it was in the "back" of the church, where there is no Communion rail.
3 --  If it had not been for the abominable innovation of Communion-in-the-hand, this would never have happened in the first place.
.
Consequently, in order for this to be an authentic miracle and not a fake, God would have to be giving His approval to the removal of communion rails, the Novus Ordo corruption, and the distribution of Communion-in-the-hand.

.
Typo --- Buenos Aires (you have Buenas Aires in thread title)
.
Maybe you got mixed up between buenos dias and buenas noches, but it's ALWAYS Buenos Aires.
.
Notice in the video, the Newpriest was told someone had dropped a host "in the back of the church."
Then they show a picture of the priest looking at a host lying on the floor near the Communion rail.
.
Three problems with that:
1 --  The Communion rail had probably been removed from the church after the reforms of Vat.II
2 --  The host would not be near the Communion rail if it was in the "back" of the church, where there is no Communion rail.
3 --  If it had not been for the abominable innovation of Communion-in-the-hand, this would never have happened in the first place.
.
Consequently, in order for this to be an authentic miracle and not a fake, God would have to be giving His approval to the removal of communion rails, the Novus Ordo corruption, and the distribution of Communion-in-the-hand.

Many of the churches in Latin America still have their communion rails. these type of 'renovations' cost money that is not available in third world countries. 

Bishop Williamson spoke favorably, if I recall correctly, a few years ago about the reported eucharistic miracle in Buenos Aries. It may have been from his Eleison Comments. I think it was posted here on the forum, but I can't find it now. His view on the subject was somewhat controversial, but it seemed to make sense to me. 

Bishop Williamson spoke favorably, if I recall correctly, a few years ago about the reported eucharistic miracle in Buenos Aries. It may have been from his Eleison Comments. I think it was posted here on the forum, but I can't find it now. His view on the subject was somewhat controversial, but it seemed to make sense to me.

Yea, I don't remember what +Williamson said, all I remember is hearing about Fr. Pfeiffer's meltdown calling it phony.  It seemed at the time that FP was right, which was an odd possibility.  Guess its easier for the NO to bring the Real Presence than for FP to be right.  ;D

But if Eucharistic miracles bring grace and good, why him? 

Sacramental grace (from the Eucharist) is different than the grace from the Mass.

Guess its easier for the NO to bring the Real Presence than for FP to be right.

The purpose of the Holy Sacrifice of the Mass is not to "bring the Real Presence" only.  Eucharist is the effect of mass, but not the purpose.  You can have the sacrament without having the mass.

The Sacrifice of the Mass is composed of 3 principle parts:  Offertory, Canon, Communion.  The sacrament of the Eucharist is PART of the Canon.  A priest, in theory, could walk into a grocery store and consecrate wine and bread in 2 minutes and confect the sacrament, but obviously this wouldn't be a Mass, and it would be a grave sin.  The Holy Sacrifice of the Mass is FOR GOD; communion is FOR the LAITY.  The novus ordo's purpose is NOT FOR GOD, it is to destroy the idea of sacrifice and replace it with the "sacrifice" of the eucharist, which is protestantism.

Everything in the first sentence here is true, but you didn't provide proof that you can have the sacrament without having the mass.  The third sentence is a supposition, a theory according to you, so we're still without proof. 

.
What would satisfy you? The answer is not found in Scripture so don't bother looking. And you'd have a hard time finding it in Church docuмents so don't bother with that either. You could simply ask a priest and get your answer, but knowing you, that wouldn't be sufficient either and you would demand to have the priest's source for what he tells you. So go ahead, ask a priest, and when he tells you, 
.
"Yes, I am able to walk into a grocery store and consecrate the entire wine section making all the wine, in the bottles, become the Most Precious Blood of Our Lord, Jesus. Or, I could walk into a bakery and with a few words and the precise intention, change all the bread on all the shelves in all their plastic bags, into the Body of Jesus. In either case it would be a serious sin, but it is within the power of any priest to do this."
.
Is that the "proof" you're looking for? I suspect not. You'd say that's just this priest's opinion. You might even question the validity of his orders. You could suspect he's a heretic. Whatever. Better yet, you can go ask several priests about it and keep track of their answers.
.
Or, you could simply believe what you are told by others, like me and Catholics like me or Pax Vobis, who have already asked priests this question. But then you would have to exercise your faith in the testimony of others, which you have already shown you can't do.
.

 Even more importantly, we aren't talking about no mass at all, but a mass you deny. Even the official Church, the Catholic Church, Popes for the last 60 years, all say it's a mass.  I don't like all this confusion, can't stand modernism, despise what modernists have done to the Church, but reality is reality.  Christ is present here. Its not like the host was actually confected in a grocery store.

.
Even if the host was confected in a grocery store, it would still be the Real Presence of Our Lord. It would be profaned and that profanation would be a serious sin, but it would be just as much the real Eucharist as if it had come from the most ornate tabernacle of the most respected cathedral in your part of the world. 
.
As for profanation, it ought to be considered that having women "extraordinary ministers" in sleeveless tops, short skirts, open toed sandals and no head covering, handing out hosts to open, dirty palms, and who knows what will become of the host once the person walks away (maybe he'll drop it in the back of the church or perhaps take it to a waiting witch who will use it in one of her OWN "ceremonies"), ALL of THIS is likewise profanation. Perhaps worse than the bakery shop version or the wine department version.
.

  Even Archbishop Lefebvre didn't say the NO wasn't a mass.  But even that isn't the issue here.  We're talking a scientifically confirmed miracle. A host, with properties of unleavened bread, from a NO mass, recognized by most Catholic authorities, including AL and even many Trads, was officially proven by science to be the body and blood of Jesus.  [No, it wasn't!]  It was no longer bread material but living tissue, despite being held in water for a month.  [Not "proof"]  It also matches Jesus' blood type, is heart tissue, matches tissue from another miracle of the Church, and is a conclusion made by dispassionate outside scientists, one of whom converted because of it all. [Not "proof"] And beyond that, it is connected with Pope Francis ultimately. You can quote theory, letter and law all you want, show the writings of men you choose to place in authority over yourself, but in the end this is way bigger than theory or supposition.  This event shows Jesus is way more merciful than people can even begin to believe.

.
There never has been and there never will be any "proof by science" that a host is the Body and Blood of Jesus. 
You're mistaken, but what else is new? 
You've been making this same mistake for years and nobody can impress on you how wrong it is. 
Science is not in the business of "proving" anything.
There is no such thing as "scientific proof." It Does Not Exist.
You can have compelling evidence, or circuмstantial corroborating facts, but you cannot have "proof."
.
Your kind of thinking is what magicians rely on to do their magic tricks. 
People who believe that strong evidence constitutes "scientific proof" will easily fall prey to a scam artist or a magician's trickery.
.