May be I don’t fully appreciate the anxiety of waiting for the decision date and the impact of dealing with a rejection on someone that young (and an unnecessary rejection at that).
But, I am thinking that, if she was my child, I’d let her know to expect a rejection, but advise her to apply even if she has very little chance to get in. In the very least, that is a full extra year for her to think about revising her essays and how to position/reposition her extracurricular activities.