Hi Nadia,
It is excellent that you are getting the testing done because this will leave little room for questioning (on their part) - facts are facts.
My suggestion is to do your research and get clear about what you want for your son before the meeting (grade skip(s), subject acceleration,etc). Use the information from above mentioned resources and the others that you find to back up what you are saying and asking.
I know this was not a lengthy response, but I hope it is helpful. I am wishing the best for you!!
