How can someone be an admin and not be in the admin usergroup?

[kh99]

There was an issue a while back where it was possible to create an account with the same user name as an existing account (or one that at least looked like it), because some strange unprintable characters were allowed in the user name. I'm not sure of the details so I don't know if, by the time it got in to the database, it was exactly the same user name or just one that looks like it. Maybe check the registration ips on both and see if either looks suspicious.

But I don't know why, if he has a primary group of admin, that he wouldn't show up in a search.

Edit: what happens if you do a direct db query like

SELECT * FROM user WHERE usergroupid = 6