When doing the Royal Trouble quest you will come across Donal who will give you a mining prop which will give you access to the crevice in the north of the Miscellania Dungeons. He can be found in Miscellania Dungeon, in the Esoterican Arms Inn.
Donal is part of a mining crew that has been hired by the Miscellanians to expand the dungeons beneath the castle, providing more living space for its people. Although he doesn't mention where he's from, he has likely travelled from Keldagrim, the dwarven capital, as there are no other significant dwarven settlements in the area.
