Archbishop Vigano was the papal nuncio to the United States. He’s sort of the Pope’s representative. More than merely an ambassador. He was also nuncio to Nigeria, simultaneously, which meant he was nuncio to more than one in nine Catholics. He has the documents to show who was told what when, available for public inspection. I haven’t seen them, personally, but it seems a very easily falsifiable claim.
What I don’t understand is the basis for his assertions for what he claims Pope Benedict did right.
I believe this pertains to Papa B's order that McCarrick have no active ministry but spend the rest of his live in prayer and penance.
Well, he would have known what BXVI was doing. Benedict laicized something like 800 priests in countries all over the world. He also retired a huge number of Bishops who were involved in devious things. He had gotten McCarrick out and removed his ecclesiastical honors and had him in isolation, basically. Francis brought McCarrick back almost immediately upon getting rid of BXVI.