With the evidence provided, i conclude that this is a case of Friendlies. Time 1:03 which at middle of the round, there is no point the guy turn zombie and the human didnt notice. Even if human didnt notice, why zombie is not knifing him for that long. And also the only way to get up there is by jumping to that woodblock seen at side where human is is sitting and viewing. AND this guy had been banned couple of times by several admins (including me) for breaking rules..
NOTE: i wont make the final judgement now instead i will wait for other's admin view since there is only one image provided.