When you successfully scry for the dwarf (need to have recruited at least 5 other council members), he should be at the axe monument.
To clear inaccessible regions, try a combination of;
- max Elven Sight and Ranger Sight
- keep any equipment you find with sight bonuses to use when exploring
- toss a teleporter stone up and teleport around by repeatedly tossing one stone and teleporting to it
- cast Wizard's Sight twice in the same location, ie cast it a second time before the fog-of-war fills in again from the first, and it will stay clear
