Damn, That cat got taken out! I never knew there was a soccer game for Kinect on the 360 that required you to kick your cat right at your camera. All I have to say is, You might want to train your cat so it doesn't end up like this one while your playing your Kinect hehe.
His friend turned the camera on at the exact time that the cat would come through? and he got hit by the cat? Nah that's too coincidental for me. That is why I say it is Fake 'N gay. Also the cat works away perfectly fine after wards...
You've obviously never seen a cat get kicked have you? You can kick a cat pretty hard and it will be fine.
It does look a little suspicious though, for the reasons you stated.