Ok, thanks Shoshon. I did try the ocarina for a while but that location seemed to come up so I thought it didn't work. Maybe you need all 8 triforce pieces? Or maybe the RNG never chose that location in my small sample of tries.
Anyway, I've now completed the game. I got up to the bonus level for selecting the third choice of what I wanted to happen but I don't have the red gem and it could be hidden anywhere and I overlooked it. Thanks a lot for it.