Unfortunately, that is all there is. If that was the only frog statuette in the game, at least it would be unique, but it doesn't seem that wonderful a treasure to go to that length to hide.
Did you also talk to the statue (save first)? You need to have the book with you that the cult members just outside Nericon's garden gave you.
I didn't. Thanks. I am assuming I need to do the Quest over right?
