I spectated this guy a few times and he kept camping the same exact spot, but not doing a single thing (he was moving around a little, but wasn't really playing the game, or trying to do anything), and his name kept changing... It was especially weird when his name included my own name. After seeing this I used admin chat to ask a mod what was up with this, and I was told to stop ghosting. What the hell?
I've seen this happen on Team Fortress 2, it is indeed a hack. My best bet would be to copy down everyone's STEAM ID with 'status' in console, do it again immediately afterwards and see if a name has changed but the ID is the same.
It can cause some major problems, believe me, happened about 2 years ago, I was given an admin status on a TF2 server I used to frequent before it was closed, the hacker managed to take the time to wait for a few mods and the owner to come on, pose as them when they went afk, and tricked the owner into giving me, a few others, and himself. The owner was able to know about it I think because I didn't have any of the staff on my friends list and that I had only been on the server for 2 months.
Yup this is a hack and whoever did it needs to be banned. If anyone sees this happening again, try to get their steamid and report it to the forums or a staff member online.