Are you sure? The most you can defenitly prove is that he killed you once while you were Unarmed, the screenshot of his kills shows only 1. Though RDming is bad, 1 rdm isn't ban worthy. (not that you wanted him banned? )
This screenshoots prove nothing really, maybe he killed you becouse he was hunting you down? or something, or maybe he wanted your wallet and you didnt handed out etc,