I will restate “you should honor your commitment” teach your daughter to say what she means and mean what she says. Taking others into account should be your priority. The world does not revolve around any one person. Your commitment today takes a spot away from another deserving student athlete. There are rare exceptions such as I rethought my major and this first school does not offer it. I can also understand if you don’t get admitted into the specific program in the university that you desired which would not allow you to pursue your career goals. Very few exceptions to this rule. Don’t commit if you are not all in.
Lastly I bet she really isn’t even that good.