You can spawn it using the ingame name of its xml instance (you know how to spawn now). There might be a Stargate Ship that overwrites it (befause of the same name, then you'd need to change the name of that unit before loading the game.
I can tell you where to find the stargate unit with the name of the deathstar for foc tommorow if needed (not on my computer now), but for EAW it should be in SpaceunitsSuper or SpaceunitsCapital.xml.