First of all: If i wouldn't think i could handle ban requests or anything that requires adminship that involves clanmates i should have never even got this position. But i did and i am fairly certain i can handle those quite well and be objective at those.
He followed the form and multiple screenshots are nice, but not always a necessity to make a valid ban-request (Sometimes you simply don't have the time to do more than one and sometimes one screenshot is enough). Fact is, the screenshots shows him being teamhit several times and after reporting them he got insulted by the guy who teamhitted him. He wasn't banned for the insult, he was banned for the teamhits. If the player that has been teamhitted thinks he was treated unfairly even punches validate a ban. If he wears gauntlets those 5 punches can sure as hell do a decent amount of damage. Yes, he stopped, but he shouldn't have done it to start with.
Punching and nudging people is generally okay and i do it all the time, but never ever punch random people whose reaction you couldn't possibly forsee.