The evidence here simply isn't very convincing. There is no ban history for Chevalier_Fred, and no way to tell if this teamwounding wasn't while fighting enemies.
I'm not calling you a liar, but I don't want to ban someone for what could be an accident. What I will do is count this as a warning towards Chevalier_Fred and if I notice him breaking rules on the server or a future ban request, I will remember this report. Probably how he would've been dealt with by an admin if one was on.
I also recommend hitting M to report intentional team wounds, and using "i" chat to see if an admin is on at the time before coming to this board, usually easier that way.