As he will probably not be granted get access to his forum account, it is advisable for him to at least re-register in order to start building up his new account.
Although OP isn't technically permanently banned because his account is locked for security reasons, I wouldn't make a suggestion like creating a new forum account. I am not sure if it's against the rules. Owners of permanently banned accounts can't participate in forum discussions any longer. Not sure how admins look at locked accounts, and if the right recommendation shouldn't be to wait until you know where you stand.