I'd much rather create a well-secured reservation/nature preserve where all the currently or even ultimately unfixable corruption victims can roam freely and do their own thing with each other. That way they shouldn't bother anyone else and the Champ will be able to re-visit them on a sex saphari, or just chill out with the non-hostile ones.
And the truly guilty I'd prefer handing over to the actual authorities (like leaving Alissa's fate up to Ryn and her councilors to decide) or just summarily execute.
I would perhaps only place in that reserve the ones that aren't fully demonized. And I'd be sure not to forget to remove any sort of wings. There's no sense in a "reserve" if they can just fly out of it.
Demons...either there's a way to reverse the process... or i'd put them to the sword.
Alissa...ehhh... If Ryn tries to spare her I'm very inclined to lop off her head with the war scythe. She's just too dangerous to be kept around...just anyone. And way too much of a psychopath to really want to have her as a fuckdoll.
As to who I'd put in a CoC2 gastigoth...hmmmm....
Byvernia, is one, she's a bit too much of a loose cannon
Pretty much every cultist that is still loose, if I don't end up burning them alive
The Horse Shaman...she's a bit of a jerk and still prefers to fuck treants
Almost all of the mercenaries
That shitty elf boy
That stink-ass earth elemental
Mayyybe the hobgoblins? They're starting to get on my nerves
The Drider Queen, she's also a bit of a loose cannon