The game lasted 545 seconds, his overall damage was 372868.
372868/545 = 684.34 damage per second.
In otherwords, this is an obvious glitch and his real damage per second isn't even close to 2000+. To prove he was here the whole game, there were only 8 people from his team in the warzone. That means his team did not have anyone who left, so there's a 95% chance he was in that warzone from the start. Hence his real damage per second is 684.34. Nice try though.
nice try grag!