I don't know... big spoilers ahead
spoiler
The Autopsy felt a little like body horror, but they didn't do anything with teeth. It also felt a little like sci fi horror, but it wasn't so much a creation as a unauthorized fucking thing, but it definitely wouldn't make me go 'cosmic.'
Folk horror also seems slightly off. I think folk horror is more along the lines of 'you're in the woods, it's dark, and you're not alone,' with the option for 'you're not alone, but there's no other person around, and there really should be.' I'm thinking of the classic grimm stories here, or perhaps the more modern ones, like my favorite horror book of the past few years: Those Across The River.