I also agree with cricket2 and MumOfThree -
every time I feel cross about results that I think are an under-estimate of her true potential I remind myself that her uneven performance on tests reflects her uneven performance in life.
If this is how he responds to testing is it indicative of how he would respond to a normative classroom? If so, it sounds crazy to put him in one, a different solution to his social needs is perhaps a better idea.
It sounds like you've found good help through the neurofeedback and other behavioral therapies, which is great! Our 2e EG ds also had a tough time at that age finding other children for playmates, but in hindsight for our ds, I feel the challenge was as much with the challenge E as it was with the gifted E - now that he's older and we have found a school situation and have helped him get through those early years of understanding, remediating, accommodating etc for the challenges, he's had a much *much* easier time fitting in socially at school and in other groups. Have we been able to find him a friend who's also EG/PG? Honestly, I don't know! But he has found friends who have similar interests and he has found that he's interested in things that other kids are interested in more so at this point - and I think so much of it is related to him becoming more comfortable with his challenges.
Hang in there, life can be so frustrating and discouraging when you're parenting a young 2e child - but it will get better. Just keep doing what you're doing - plugging away at understanding and trying to get him the best support and help you can.
Best wishes,
polarbear
ps - we also never applied to DYS for our 2e ds - when he was in early elementary, his WJ-III Achievement scores were too scattered due to his challenge E, and to be honest, I didn't see that it would offer up anything that would be helpful enough for us to bother putting together a portfolio. We tried instead to help with the high ability through making sure ds had projects/reading/videos/etc that would stimulate his brain (in areas he was really interested in) while we plugged away at helping remediate/accommodate/understand his challenges. Once he reached middle school his achievement test scores (with accommodations) started to correlate much more with his ability. We still haven't applied to DYS because it's not something we've felt we needed to do at this point, so I'm not sure what type of achievement testing is used at middle school level - but for other talent searches you can use Explore/SAT/etc scores - and ds has done *much* better on those types of tests.