It sounds as if they are introducing a fuzzy criterion so they can tweak their numbers - test results being correlated to SES being correlated to race and ethnicity as they are. As others have said, it is sad if access to a gifted program is to be determined by policy considerations rather than need, but it is what it is and you do think it would serve your daughter well.
The worst thing for her would probably be to sound coached, or hothoused, so I agree with the others who suggested to make sure she is well rested and fed and tell her to just be herself. Maybe remind her of what she is enthusiastic about, in school or outside academics. I like the idea of doing an activity in the days leading up to the interview that ties into her enthusiasms and interests. Just not something that smacks of money being thrown around.
