So I got the statue at the end of the maze, went back to the red mark on the ground, got crushed so it opened, respawned at the statue, the hole was still open, so I went in, got the coin and couldn't do anything else.
Did you click on the grate to open it? It is above the coin, it leads outside.
I did try that, I might give it another go later and get back to you : )