You cannot delete the units but they are not null and you cannot see their bodies. This only seems to apply to other player bodies or the player's own body.
The ideal system would be that the vehicle cleanup manager dumps the bodies then deletes the vehicle if needed and the bodies get deleted within the corpse cleanup manager.
// Description.ext
respawn = BASE;
respawnDelay = 0;
respawnDialog = 0;
respawnButton = 1;
disabledAI = true;
joinUnassigned = 0;
respawnOnStart = -1;