Find Galen in Grenth's Footprint, talk to him and lead him to Sorrow's Furnace. Upon accepting the quest inside, Galen will cast Chains of Enslavement on the party, with the effect that all Stone Summit become friendly to the players. Once the party has been "sold" to Taskmaster Ironboot, follow him to your "slave master", Krak Flamewhip. After scouting all the places required and completing all five sub-quests, return to Galen for your reward. However, you can also choose to not complete any of the sub-quests, and just scout the areas.