I want to create 3D stereo pairs from the game, to watch them in Google Cardboard

That’s pretty much how it works for 3d images.

You need two perspectives, one for each eye. Then you split the horizontal resolution in half and put one on each side. You’ll have to figure out the necessary angle between the two images yourself, but that’s pretty much all there is to it.

You don’t need a ship for it, the pod is sufficient. You don’t even need to move the pod. You can just use the other camera … the not-orbitting one I forgot the name of. It allows moving the camera to move freely, instead of rotating, which is perfect for your usecase.