I understand the desire to find the "perfect" school that will solve the problem of challenging your DD who learns differently - but this school sounds like it might not do that (and honestly, we've started to conclude that such a school might not exist for our DC).
We have a VERY $$$ "gifted" school about 25 minutes from home, but the admissions requirements are actually slightly below our local PS's G&T program. While the local PS's G&T program is not perfect (for one, it starts in 3rd/4th, like many schools), for now, we are sticking with this option. We also have very good PSs overall. We feel there is a value to having our DC socialize with their neighbors at school, and also at home. It may be that you are trying to choose among the lesser of all evils.
Have you effectively "maxed out" the available resources at the public school? Are there possibly any other resources that might be explored? Some "not so well known" "challenge" programs, perhaps?
I certainly would not let the school rush you into a decision that you are not ready to make - especially considering the financial investment involved.
