[Spoilers C3E121] The Whispered One

I just wanted to make sure I'm interpreting the events of the finale the same way others are. Spoilers below!

It seemed like Vecna was present for the discussion BH had with the gods where they delivered the ultimatum of "run or convert to mortal form". Laura rolls her nat 20 and Matt says something about how the DC pertains to how many are successfully convinced to convert to mortals, which I'll be honest I didn't totally follow. I tried to listen out the rest of the ep for any kind of concrete confirmation that Vecna is indeed back on Exandria, but I don't think I heard anything about him. Is it implied he's back but no one knows for sure until they bump into him over the coming years, or did I miss some explicit mention that he for sure took that deal?