Ok, I went to the cave with the bronze dragon where the depository box is. There are some crates at the end of the hall and then I start to walk down the corridor towards the dragon but I get halfway and I can't get any further, it just bounces me back. The narrator says maybe the is another way in but I have been everywhere outside and I cannot find another entrance. Please help. I have been working on this for days and cannot figure it out. Thank you.

The crates give you a hint: try the stout mines first. They might have a solution.