I mean, why if she knows the cards/runouts would she have gotten it in on previous hands drawing literally dead?
Just to set up her BIG MOMENT of getting it in with 47% equity, and also agreeing to run it twice, so whatever cheat she has would have to know the second card after the natural river?
It just makes no logical sense whatsoever.
My best guess is she has some sort of read/tell on Garrett when he's bluffing/semi-bluffing and obviously doesn't want to say that and give it away, so comes up with other nonsense.
My second-best guess is she just decided "he doesn't have anything, I'm tired of him running over me/the table" and called without pondering the equity of her nothing. I've seen plenty of players call in spots saying "I didn't think he had anything" or "I thought he was bluffing" when they literally can't even beat a bluff.
My THIRD-best guess is she was remembering the J3 hand she had the literal hand before. She said when she was looking back she was checking to see if the J was a club.
I just can't find any reason to have an amazing elaborate cheating system set up and you only use it to get in on the slightly bad side of a coinflip.