I don't have a problem with her quitting when it's obvious she's in last place and it's just a guessing game at that point, but I am upset that she didn't study better. She really dropped the ball.
I don't think she can say anything to change her mind. She knows they need to be split up for sure, and I don't blame her because if I was Ash, I'd easily split them up as well. 2 is better than 1.