Why does her returning the chips matter? Are you not familiar with how chronic cheaters operate in pretty much any other field?

From fighting games to Donkey Kong to fishing to whatever else you can think of, people that chronically cheat often have the mentality to double down and/or muddy the fields to try and disprove that they're cheating. Because the best counter to any sort of cheating accusation is to never fold. This is even when they're explicitly countered with hard evidence of the cheat.