I assume a snake lock is some sort of cable with a lock at the ends. In your case, assuming you cannot get the key to work the easiest option will be to get a pair of bolt cutters and chop the cable. Perhaps a locksmith can get it open for you. Is it possible to pry the bent piece back out?

If the lock can be that badly damaged simply by trying to insert a key, then perhaps you should rethink your locking strategy.

Freezing and smashing the lock, even if it worked, would require something like liquid nitrogen. Contrary to popular legend, air conditioning coolant - freon - does not work.