I think MOM will call in Z’s Mom and she will say it is Z’s voice screaming for help.
That’s good and all but the defense needs to hammer home the point if GZ saying he was screaming for help when interviewed by the police right after the shooting. He had no ideal a 911 call captured his screams at the time so it corroborates his story and also they need to hammer home “Common sense” in saying that the physical evidence clearly shows who was screaming for help.