1) A navy sleeve is allowed if it's one of the school's colors -- it needn't match the jersey color. But, all sleeves must match (so one white and one navy wouldn't be allowed).
2) Different states treat the "medically necessary" requirement differenetly -- some require a note, some require an oral confimation, some don't even ask.
3) You were the R -- act like it.
It's the same as any other rule dispute between officials -- someone needs to take ownership and be responsible if s/he is wrong. In this case, since it was identified before the game, perhaps one of yo could have gone back to the locker room to find some state requirements on this to convince the other.