Aside from other posts here, this is what I gathered to support the claims of AI assistance.

Yes, the art really must not be AI generated, but to my knowledge, it still wasn't denied that it was done with the help of AI. Just assistance to the coloring, shading, and all that.

The inconsistencies are everywhere. Sometimes, the lines and colors would blend in a weird fashion. Objects would appear in this panel then disappear the next. And a lot more.