I didn't see evidence of that in the videos I saw. There seemed to be no wounds on him except the head. The people that gathered around him couldn't figure out where he'd been shot either, because his shirt was off and tangled around his face. It had been used as a sort of hat as he ran at Rittenhouse before the shooting. The only obvious wound was in his head, and he looked like someone with a traumatic brain injury. He wasn't dead, but he wasn't responsive either.
I could be wrong, but that isn't what I saw, and though there were others firing guns around there, it looked and sounded to me like Rittenhouse fired four times.
