I'm more concerned with the if the creator has an issue, I like making sure of this stuff. Why would Twitch have an issue other then it being Mature?
Viewing post in It it okay to stream this game on Twitch?
You shouldn't worry about what creators think, you're taking free products available without any license terms and do them free advertisement no matter if they understand it or not. VotV's dev is definitely not against it as it seems, there's a ton of VotV content around, including the game's files publicly available on the wikis ripped out of the game, and the dev is chill about it.