You know that this kinda of stuff rarely happens? Its rather people being dumb and running into them. I would still not really do something about this. There are genuine mistakes that can happen and I run into this kind of stuff from time to time as well, where I legit cant see the little T (especially if they got a skin and its halfway in the skin) above their head and shoot them and maybe kill them. I guess I was just lucky that those people understood that this was a mistake (I at least revived them afterwards if they died through me). I wont deny that this is RDM and I know that when this kind of stuff happens to some User on the server that we punish them for it (I would rather not, but I am not allowed to just say no to punish someone who did RDM when the victim wants him punished), but I would still say that I wont think anything major will happen to broken. Especially because he already admitted to it and apologized