I would first do what I can to ensure DD gets the score she needs, because if that can happen, problem solved.

She seems to already value doing well, so that's a big part of the problem solved. As a next step, I'd see where I can find practice materials and test her, to see if there are any skills she needs to work on. Is she managing her time well, or is she getting anxious about the time limit and rushing through? Is she reading the instructions carefully? Are there any skill areas that need some review? Etc.