...our EG ds was also proclaimed "not gifted" twice by our school district - once in spite of scoring > 99.9th percentile on his IQ test but slightly less on his achievement test (he is a 2e kid).. another time because he scored lower on the CogAT, which is a test where HG/EG kids sometimes don't achieve scores similar to other tests.
I could have typed that exactly for our 2e child; that's exactly what her scores looked like including with the CogAT and we, too, had quite an uphill battle to get her school system to recognize HG+ scores as gifted at all.
What I'd be looking for, based on our experience of repeat IQ and achievement tests with a 2e kid and talking with other parents of 2e kids, is wild variation in scores between and within indices and a lot of fluctuation between different testing sessions. For instance, our child had some indices that looked mildly gifted, but had scores ranging from high average to the 99.9th percentile. In a child who is, say, moderately gifted not highly gifted+ that might shift down on all parts a bit. As an example, you might get a 30th percentile score averaged with a 98th percentile score which makes the whole index look high average or just plain average.
Since our child is 11, she's also taken a lot of achievement tests over the years in school. Along with repeat administrations of IQ, we have a distinct pattern of wild fluctuation from one testing to the next. We've seen achievement scores go from high average to the 99th in the course of a few months as well as the reverse (upper 90s to average). Two administrations of the same IQ test one year apart led to parts that were at the ceiling one time being high average the next and the reverse for other parts.
Someone who is only looking at the overall number would fail to see a much larger picture here.
That said, like others have mentioned, even if your child is not 2e and is bright but not technically gifted, he is still the same child. 2e is not something I'd want truly. I know a lot of very successful children academically some of whom are straight-A students, some of whom are subject accelerated, etc. who are not gifted. Average or bright-average with the right personal characteristics can sometimes take one a lot further than 2e and/or highly gifted.