I will be absolutely fascinated to see how you end up writing endgame Chris/Victor. I mean, I guess I'm an endgame Victor/Yuuri shipper, but I hesitate to say that because it implies being dogmatic and unwilling to read any other take on the situation, which I'm not.

Really it's not terribly difficult to imagine Victor and Yuuri falling apart in fairly short order. Maybe Victor burns out, faced with Yuuri's impossible expectations and the impossible task of coaching and competing simultaneously. Maybe that "let's end this" in Barcelona is just the start of a great deal of on-again, off-again angst. Maybe Victor thought they were engaged but Yuuri really didn't mean that at all (I disagree with this strongly as a canon interpretation but it can work quite well in fic). Maybe Victor really is as fickle and selfish as Yakov thinks, and entirely believes that he will worship Yuuri forever, but gets distracted after six months.

Maybe the fic just starts with Chris and Victor meeting in a bar somewhere and Victor shrugs and says "let's not talk about it tonight."

It's all good! And it baffles me how many people in the fandom are absolutely allergic to Chris/Victor. It must be too much mature Eros for teenage fans, or perhaps it's just because it's the only obvious threat to the juggernaut pairing.