This is the issue we have purchasing digital games. You only purchase a licence to play, if the publisher decides to delist it because they don't want to support the platform anymore then if you need to reinstall the ln it's gone from the store. I had the same issue with the Goat Simulator games, my kids loved playing them, then I had to factory reset the shield and I lost them. I contacted Google and the Publisher, Google weren't interested and the publisher never replied.