I have the same problem. I finished the main story but did not find any way to get into the mines on the mountain in the south of Lapolin.
I have almost done all the tasks. Only 2 tasks are missing.
Catoriomna is no longer talking to me, so I can not solve her riddle.
And Joava wants more news. I have already provided her 4 news, but there is still one missing.

I would also like to thank again for this fantastic game. It gave me a lot of pleasure and the german translation was really good (I think better than my English ;-)  ).