Regarding the art compilation at 2:02, yes it's very likely AI generated, here are some tells:
1- right side castle 'drawn' as if it were much farther away judging by the perspective, and position relative to the left side castle
2- common AI artifacts, nonsense smudges, most arts picked got away with these due to the dark fantasy theme and rough style
3- same prompt used for the 3 arts, little sense in paying an artist to draw the same shit thrice. The same thing can be said for the entire compilation actually
4- cave with the horizon visible but there is a huge mountain or wtv behind it, that is still possible if the mountain has an improbable hole coincidentally in its non visible part but artists would avoid this type of confusion either way
5- nonsense smudges again, sky invading the castle at the top, and walls invading door space right below
Been fiddling with AI shit lately but I'm no specialist
And dope vid, 50 50 over that thing was pretty nice