Hi Dustyn,
I work for Swell Rewards (Loyalty Rewards App). I will talk to the developers and see if that's something we can add. We are constantly adding and updating as we grow.
You should check us out. We do allow some customization, but not enough where you can put everything in Spanish.
Good luck with the store! I'd be happy to demo/go over any questions or concerns you had with the app.
- Mike