MAME says 5201-5 (switch 5) causes this game to freeze but "5201" seems to correspond to a memory region inside the game data rather than a switch on the board. MAME's documentation of these machines is almost nonexistent unfortunately, a lot of the MK4 games in MAME were acquired as just the EPROM chips without any boards to test, and the service manuals used for documentation seem to be for either the older MK2.5 machines or possibly the Australian versions.
That said, the game won't respond to anything if there is an error either so I don't think the dip switch is the problem. Even having the main door open is enough for the game to not want to enter the audit menu. What happens if you run the machine without the bill acceptor?