What? That's easy! I bet anyone with a 1500 level tactically can see that. (also, why do you call Bb2, and some other moves, a blunder? they're not really that bad)
Also, I think you should have reported this to chess.com directly, not on the forums. Posting this on the forums, accusing people of accusing you of cheating, might get you in trouble! (I think that might be in the rules or terms & agreements)
15... Bxh2+ (which you mark !) is actually (?), it completely misses the mark. The correct tactic is 15... Nxd5 and white cannot recapture with his queen. 15... Bxh2+ throws away two pieces for one piece and a pawn.
You're absolutely right. I was focused so much on move 22 that I completely forgot the point you made.