You are correct, they used it for production, building the scenes, getting camera data. I then assume they exported the scenes and camera data to whatever they

You are correct, they used it for production, building the scenes, getting camera data. I then assume they exported the scenes and camera data to whatever they used for the final render. So Unity was used for 70-80% of the work. It is possible but I don't know. Just was trying to point out that it's more than just some demo that it was used for.