Of Orcs And Men

The first time you reach the Black Hand camp, make sure to talk to all of them, especially "The Lost". Afterwards, talk to Spearhad about "The Lost". He will tell you to inquire why "The Lost" will not talk to you. The next time you arrive in the camp (after the Sarkiss mission), talk to Spearhead again and he will tell you the reason why "The Lost" does not talk to you is Dorek. Afterwards, inquire with Fox about Dorek and where he hides. You can travel then to his location and try to take him out. Be warned though that you have to fight him and around 6 guard dogs. The pack of dogs can dish out some real damage, especially on expert.
As Arkail, use Rage to HP conversion, Provoke and always stay in defensive stance, taking out the dogs first (those also targeted by Styx). Make sure to resurrect Styx as soon as possible. Same for Styx: as soon as Arkail goes down, resurrect him and switch back to Arkail to control the enemy. You may die a lot (did this on Level ~ 8 on Expert).