I do wonder if they'll make changes in coaching arrangements after this season. Obviously a high-stakes competition like the Olympics carries consequences for the relationship between students and coaches, especially considering the difficult balancing acts involved at that rink. If P/C and Romain feel even the tiniest awkwardness regarding training there, I think they'll make a move. They can afford to do that. (Of course, the non-skating training team seems very important to them too. Not sure if that is easily replicable.)
If V/M retire, I strongly doubt that there will be any reason for them to change.
I don't know how they feel, they may be a lot more spiritual than I am, but I still have a very hard time to digest what happened. But that doesn't help, it is what it is, and they have to move on. It's their life, and they are so extremely talented that even without this gold they can still beat every record in ice dance. There's brilliant stuff for them to do and explore, and Gadbois has been really a miracle for them. Yes, the costume malfunction is something that should make everybody in that team think, and yes, if V/M hadn't been there, probably there would have been more attention on it to avoid it from happening at the Olympics. (On the other hand, if V/M hadn't been there they would have had gold even with all that misery...)
Anyway, if V/M retire, the situation will be different. They get along famously with Madison and Zach and most probably with a lot of the other Gadbois skaters, so I don't think that kind of tension situation will develop among the present teams. You never know what happens in the future, but at the moment, it seems like a very stupid move if they would change coaches. Especially, as you mention, with their present super off-ice team. But I think that their relationship with MF/P is also stronger than the dress disaster.
I apologize for not mentioning Icetigger in the post you quoted. They were the one who pointed out (before Alain) that this hickup was really avoidable and amateurish. Sorry, Icetigger! I edited the post but should have remembered that when I wrote it.