Your question carries within it its own internal contradiction:
Since the fssp does not believe the v2 docs to contain errors, it is not possible to attend a mass in which the integral faith is upheld.
Look, Sean. Father Bolduc told us not to go there for multiple reasons, including the fact that an intrinsically evil act is going on there DAILY. The "Latin mass" is being allowed to co-exist with the Novus Ordo at that ICK mass, and I will not go there until that stops. Also, there are novelties being done at this church, and the people that go there are hodge podge about their Faith. Some see no difference (and believe me, I lost a "friend" of 19 years over this) between the "Latin mass" and the Novus Ordo, yet they go there. Also the women are mixed with the head coverings, some outright refuse to wear them. There is no combat against the Novus Ordo, and there was a "mass" where women were "presiding" going on there (I personally know eye witnesses to this atrocity.)
Also, do you REALLY know if the host you're getting is one from the "Latin mass" or one from the Novus Ordo? I don't, and all I have is the word of the priest, whom I don't trust anyway.
Fr. Bolduc told us that the Diocese would have recognized what he did if ONLY he would say ONE NOVUS ORDO! And he WOULD NOT COMPROMISE and do that. How many ICK priests have done this, and concelebrated Novus Ordo masses to be able to be "approved" by the Diocese? Probably every single one of them. So don't tell me I'm committing some kind of sin by not going to Fr. Themann's church and the ICK masses. Also, Fr. Themann accused my mother of interpreting Quo Primum "according to Mrs. ____ " Yeah, okay, Father. We were interpreting it according to what it SAID, not what HE wants it to say. He's saying "well some of it is disciplinary and some of it is dogmatic." Well that's not the way Father Bolduc taught us what that docuмent meant. As far as I'm concerned, he's misinterpreting an apostolic bull, which makes me wonder whether he's a heretic or not (forgive me for saying so, but what else can I deduce from that kind of reasoning?!)
So until the neo- SSPX is gone, or some miraculous thing happens where the ICK stops having the Novus Ordo said at their chapel on the Diocese grounds, then no, I'm not compromising going to EITHER ONE of them. Both of them, as far as I'm concerned, are being done in a displeasing way to God.