He has pushed passed a limit/boundary and continues with exhibitionism. It seems to me that would be good enough.... If you are so uncomfortable with the exhibition .. and his threatening denial by removing himself or cutting off communication ... I find that problematic.

From where I stand as Dom, to me and me alone ... I find absolute submission to be a very difficult demand to impose. Others expect it and all the rigidity that goes along with it ...

I don't know how the rest of the relationship is .. so i find commenting on other parts not within what you wished to know.

Ultimately ... I think what he's doing is wrong. again IMO. And I've got a feeling that when you confront/talk to him about it.. you may find his view of absolute submission leaves you out. Some just have a very different view of what D/s is all about.
I hope things turn out better than that though.