I will note that being new at this I was really over thinking this. Maybe you are too? When trying to get the ticket printer set up and seeing "make sure that there are no credits on the machine when using the Key Chip", I figured out that it's as simple as pressing the cash out button (two times)which will put the machine in the attendant call mode. The attendant would then use the operator key (or Jackpot Reset Key #2341) that fits in your upper right side of the machine to clear the machine and hand pay your cash out.
Oddly enough, this all started after I had just gotten the bill validator to take $20 for the fist time and I ran the credits up to like $260 on 9 line penny machine. This rarely happens to me at a real casino.
Jim