Ah, so it allows them to have spectators. (Who talk a lot and get in the way...)
But couldn't he still make a default minigame with tdm, putting everyone who joined onto the spectator team with no tools (or some harmless ones for them to fool with) while he got the normal tools? If he didn't want killing, just don't give any weps or turn off weapon damage. Either way, I don't think this needs a new addon.