Well, that’s all the hooks and crooks I know about.
There was a longstanding bug report about not being able to create AR characters even after a complete and correct unlock.
There wasn’t an obvious resolution, so maybe you have been caught in an instance of the bug that isn’t related to (for instance) Newcomer status.
Oh, one other thing: Do you have any other characters in that account that are still in Newcomer status, or were created as Newcomers and you haven’t played since dinging 50 on your main? That thread has at least one report that an alt was making the Newcomer status stick to the account even after the main cleared it, simply because the player hadn’t logged into the alt after getting out of Newcomer. Seems very weird to me, but I figured I’d mention it.