What exactly makes you think this person has been locked out/down of their account? Are they unable to sign into their account? Are they unable to access their profile?
Regardless, I don't know for sure since I've never been banned or known anyone who has, but maybe you could message a moderator regarding whether this individual was banned or not? I'm not sure if moderators can disclose this sort of information or not publicly though.
You can tell if a user is banned, usually because their usernames are a lighter shade of black. You would not be able to Private message them, or send them visitor messages.
You can tell if a user is banned, usually because their usernames are a lighter shade of black. You would not be able to Private message them, or send them visitor messages.