There seems to be an error in the ciphertext, making the word “was” come out as “oas”.
The remaining seven stones don’t have an encrypted inscription. They look nice anyway. This is stone number 3:
And here’s a plate giving some information about the collection:
All in all, I enjoyed my trip to the Cheltenham Listening Stones very much. I can only recommend going there. If you want to see more, here’s a short video:
Further reading: Who can break these three encrypted postcards?