Schism over altar girls? You're kidding, right? That would put the Holy See in schism with itself: "nor require that priests of the diocese would make use of female altar servers, since 'it will always be very appropriate to follow the noble tradition of having boys serve at the altar'" (Card. Medina, Letter 2001).
1. Buy into Sedevacantism, or
2. Buy into the New Theology of a counterfeit Church.
Of course, while all the acting as if you believed neither is an option. As for myself, I would firmly state that I would without a doubt reject either option.
I have no real confidence in your sincerity. I would love to be proven wrong on that score.