My first thought was not, as perhaps it should have been, to message an admin, but to spectate and record this player in the act of what I perceive to be hacking.
When I first noticed this video I did not think it was enough proof but it was worth investigating.
I found him on another server and caught him aimbotting, so I can tell you that hes banned now.
Thank you for reporting anyway.
Tip: [Z][X][Y] ← use these keys on your keyboard to toggle pubvl features, mainly X because it toggles the ESP and that helps greatly when reporting for ESP.