Well, if you feel very strongly that the program in question is one that would benefit your child educationally in a really substantial way, I'd be collecting additional supporting documentation-- portfolio items, basically.
"Gifted" is a range, and it isn't really something that is very well captured by conventional numerical methods. So the short answer is that yes, it should matter since most programs have more than one means of qualifying. Not all children test well.
The longer answer is that a lot depends on just how close that FSIQ value is to "the" magic number, how rigid those who decide tend to be about the numbers, and how much your child is in need of the things it would gain him to qualify.
Also worth considering-- is this a one-time thing? Or is it something that can be revisited in a year?
