Sorry to burst your bubble,
There is no simple way to Perm-ban an account in ONE shot!
It takes two shots, at least!
Transfer the character off, have a friend use a program such as cheatengine or WoWInfinity to get the char 3 day banned, and then permabanned. Chances are, if you get the acct 3 day banned, it has a good chance of being locked for an ownership dispute.
Whichever way you go, good luck!