In Katheryn's Mole Insider, she says she was there, watching to make sure no one missed their turn or hit the ball out of order, as were a number of other people. I don't think anyone tipped the producers off. I think the crew reviewed the tapes and discovered it for themselves.

Someone might have noticed during the game, but I think they let it go at the time because you can't have some random crew member go, "Hey, it was Darwin's turn, and Dorothy went!" Plus, if they're wrong, that screws up the game. So you let it go, and bring it up dramatically at dinner the next day--adds a little plot twist, if you will. Plus, it keeps the players up forever, makes them tired and crabby at each other, as well as fostering ill feelings toward Bill since he was offered the exemption rather than the rest of them. Classic Mole.

All that to say--I doubt the Mole had anything to do with telling the producers that there were multiple slip-ups.

-WtM