The journal mentions a "stronger pull" for the compass. If the spirits of this place are indeed tied to it, they may serve as the pull we need.
I've come upon several locations in the pass where restless spirits tend to appear. Perhaps if you show the spirits there the compass, they may be able to help point it in the right direction.
You seek these locations out. I'll continue on to Karazhan and see if I can find anything leading to the Dark Riders.