GodlyHerb, your ban has expired so you should be good to go.
StonedSteel, you'll need to PM Canary or someone higher up the food chain if you'd like to question this issue on theft.
While anyone would agree taking money from the guild and then promptly leaving is a douchebag move, if you gave them rights to withdraw from the bank, it's going to be seen as your fault.
Personally, I'm not sure it'd be safe, much less possible, to police something like that. It's really up to you to protect your own bank. Unfortunately.
Again, feel free to PM someone though. They probably can't help, but it never hurts to try.
Locking thread.