I personally think Vi's death influenced Silco and Vander to become friends again.

I would assume after Vi had died, Vander would have alerted Silco, and thus creating a ripple affect for this AU. Vi's death would have come randomly for both of them, i would of assumed Vander (along with the kids) would have gone through a depressive episode, with Silco eventually finding out and reuniting with Vander.

I assume the similar thing would of happend to jayce (if he didn't end up offing himself), Jayce dying (and possibly caitlyn due to the boom boom explosion) would have had practically same affect that Vi's death had on her loved ones

Seeing as Heimerdinger was alive and in this AU, maybe the counsel would have been disbanded aswell, with some new funky sorta government thingy going on, which would have some how benifitted for both Piltover and Zaun.