This really is a lock because Lovelady did say that he was "on your top level" and he also said that he was visible in the Altgens doorway. Since we know he wasn't Doorman, there is only other man he could be on the top level, and that is Black Hole Man. You know he wasn't Black Tie Man because Lovelady didn't wear business clothes. That leaves no one else but Black Hole Man. Hence, Black Hole Man was Lovelady.