We have a guy up here that buys those type machines and puts them in lil mom-pop stores and services /refills them.
Any of those type guys should have a master key, the guy I watched (He had them in my video store) used 1 key for all 4 machines.
Look in your phone book under vending machines or concessions.



A name of the machine might help chase something down.
Just a thought, the machine might have belonged to some else and was put there on percentages.