Interesting idea, but I hesitate to build anything that might be torn apart by a drunk looking to get more money for booze.
(Also why I don't do Battlebots - I don't spend hours creating something just to see it destroyed.)
How I *would* do it though, I can advise on. I would combine the following two items. They have exactly the functions you are needing, they just need to be MacGyver'd together. The code is two digits, let the first one be the "start" button, the end of the maze be the second number contact point, and the wire in-between be any other number that will reset the lock. runs Safe runs off 4 AA's , the Buzz Wire game, i dont know.
Who knows? with enough incentive, I might be willing to tackle something like this, if I can find the parts lying around my room somewhere. \
aka The Other David
"In Theory, the is no difference between practice and theory. In Practice, there is."