I don't think it's too soon.
Maybe he and his friend would benefit from curriculum compacting?
Your plan is better, but a harder sell - start there and have a few 'ok' options in mind.
I wonder how he would have done on a Math placement for the year above - maybe 50% also - there is so much repetition in Math.
If the rest of the school is a good fit, you may just have to do Math privately. Some schools will let you hire a tutor to work individually on school grounds during Math time.
Sign him up for the SAT ASAP, that might make an impression with the school, and at least he can do 'big math' with peers at CTY summer camp during the summer.
See if having your family consultant talk to the GC to explain 'how these kids can be' is the best way to get the rate answer addressed.
Least-worst!
Peace,
Grinity
