Do you have any proof? Cause last I heard nitro said he is not using AI.
I don't know what would you consider proof but Vi's animated scene is very obvious (typical glossiness, blur here and there, noise textures to hide minor AI mistakes) and in this animation you can even notice how the dick's colors and textures change from one frame to the very next one for no particular reason, while the seemingly handdrawn veins remain consistent.
To me it clearly looks like there's AI and traditional art elements mixed now.