I would have looked for the hidden camera - cctv etc, thinking it was a joke / set up
If the bank was open I would probably go in and inform there was a problem. The bank will find out anyway and have a record of all withdrawals made.
If the bank wasn't open I would max out my card and keep the extra money for a certain period of time (at home of course - it earns more interest there

). If it wasn't asked for after 6 months I would spend it.