The prize goes to MVD. She nailed it.
They showed the strategies of Mark, who won.
They showed what the mole messed up, who was Craig.
They showed these little clues which told you the final 3 players were and who was the mole. During an interview with Clay, there were two small figures which looked like lower case i. At one point, they digitally changed the background to show 4 "i's", hence four-eyes who was Craig. The dungeon one where they had to grab a key and go for supper, Mark was against the wall and behind him were the letters CRG scrawled on the wall.
Remember all those ties in early executions, Mark was tied with at least 3 different people but only stuck around cause he did the quiz faster.
When Clay was eliminated, it was because he and Mark tied. They were both guessing Nicole so Mark figured it couldn't be Nicole and had to be Craig. He didn't know who the mole was until almost the end.