Doriam Muldevar is one of the few people in on the joke, and has promised to help the Doctor keep his secret. He's also apparently an accomplished hacker and is armed with a media chip in his head, excellent wi-fi in his crypt, and nothing but time.
As for the slaver's database, the Doctor is a time traveler. He's been to the end of the universe (well, close enough), he's attempted to kill a caveman... and he's spent an awful lot of time (~200 years) running from Lake Silencio. The Doctor is known throughout the time and space, and feared by much of it. That's kind of the point of a Good Man Goes to War and the Pandorica Opens. "Status: Dead" wouldn't keep him off the database.