Depends a bit on your state regs. If you're required to state the defect in the school's eval, it might be a bit more challenging, since there isn't definitively an obvious thing to point to. If you're not (i.e., you can generically dispute the findings) then that would be something to consider.

Also think about what you hope to obtain as a result of the IEE, in terms of specific accommodations, specialized instruction/services, etc.

...pronounced like the long vowel and first letter of the alphabet...