I found the easiest way to get this is in a game or two of Skirmish. The Skirmish game mode is 3 vs 3 deathmatch, and it's the final unlockable game mode.
The focus is not just killing, but resurrecting team mates is key too: your buddies tend to 'bleed out' over a longer time and they can't force their resurrection for a few seconds. Which gives you more time to get to them. When you reach them, hold X over their remnants.
So play this mode, stay close to your buddies and you should pop the cheev quickly. I had played probably 30-40 games and not resurrected anyone until I played this mode and got the cheev in the first game!