Dwarves who visit the cave will note that it is not naturally occurring. It appears to have been created with picks, shovels and other mining tools. The technique employed was rather crude and definitely not the work of dwarves. In fact, the cave was created by knockers, the same kind of creatures that may have been encountered in Hex 001.
This addendum will tie in nicely with something I've prepared for Loviatar #8.