There's opposed, and then there's opposed. I doubt many priests in the US district are in favor of joining with NewRome. The problem is, they have a blind trust in Bishop Fellay, and just think they have to blindly obey him, that he knows best or whatever, or that it's just a tactical error but not the end of the world and you have to go along with him. There are very few who are against it enough to speak out, like the few Resistance priests have.