Private message from somebody that would know the story.
I finished the game with a single Vega (with a massive overclock). Waiting to see if there is any Big Navi news in March. If so, that's probably the way I'll go, otherwise I'll toss a waterblock on one Vega and crank it up some more.
Also running two vegas. Just bought the game.
Have similar problem driver hung etc. etc. Turning shadows off can make it run but the performance is abysmal.
Very close to just selling second vega since it feels like MGPU is just never gonna have a future.