There is a legal situation here. The characters are your property, as you said. He is going to post those without consent. The scenes are your intellectual property and you most likely have the documentation, as the developer, i am sure.
artists are still bound by law. I went to art school and they taught us the legality of documentation and consent.
Thankfully, yes I do have the documentations. You're correct on that by all means, but I'm unsure why he refused to believe me and stated that it is my opinions, not facts. Whatever he is on, I'm confident he's beyond help. With this public knowledge right now, his artist career will never recover. But honestly? I really hope he change his mind when the audience start to call him out on this whole matters (Only if he begin to post the CG scenes).
He is also more than happy to block anyone who tries to call him out, so that would definitely turn into legal situation if he proceed to refuse taking it down.