That was so close you could argue either way on the call.
By the letter of the law, yes it is a hand ball.
By the spirit of the law, wow, it is really tough to have that be the outcome of a match, let alone a state championship. Especially if the kid is only a yard in the box, and it comes off of a rebound like that.
The referee did a good job selling the call, if you slow the video down and then pause it, he is the only one signaling for a handball, none of the HHI players are.
In my 25+ years of experience I wouldn't call it, however, I can't argue against it being called as well.