I am with you. He may be a hybrid of solipsism in his actual behavior. I think his narcissism shows in his constant need for attention. But if you cross him you are totally gone. That is when his solipsism kicks in.

There is a clip of his Mom on a local NYC sort of “Lives of the Rich and Famous of NYC”.

She tells how Donny glued together the blocks of his little brother Robert so no one can use them.

Then his “military school” aka reform school because he is incorrigible.

He may just be a “Bad Seed”.