Quoted from sped372:Everything was working properly and then we left the game on (in game over state) for a couple hours, not sure if that's a clue or not,
This may actually be a clue. There are a few relays that stay energized whenever the game is powered on. If you left it on and in a game over state, it is possible that one of those relays (its coil to be exact) just gave up. Those coils are on all the time and get hot and eventually fail. Without the manual or schematic, I can only guess what those relays are called, but it might be a good place to start looking before you start messing with switches that were working fine just a few hours earlier. Your schematic will show these relays in the circuit diagram close to the transformer on the sheet. Your game manual if you have it will tell you what these relays are when you look at the start sequence.