Piepacker has Spacegulls as a built in game added by the Morphcat team They are partnered with each other and also the survive is free with the game The game runs the same as the emulators

To sign up and play https://beta.piepacker.com/

Homepage and info https://piepacker.com/

I don't see why it wouldn't be allowed. Just state that you're using it when submitting a run, please.