I was working on the assorted Blackburrow quests and was trying to find my way to Guard Ellery for the quest Run to Daylight. When I got to the ledge, Slavemaster Raouk was up there as well as 3 other gnolls. Great I thought, I need his finger for Send the Message.
While Raouk (level 81) is flanked on either side by other gnolls, there was a fourth behind you to the right when you come up the bridge. That fourth one can be pulled without agro'ing the others. I was then able to monk pacify one of the other gnolls (could not mez Raouk at least) so pulled Raouk and his buddy to the previous platform and solo'd them there pretty reasonably with cleric merc. Did this at 81, ~750 aa's, 80-85 bazaar gear (so most items ~800-900 hps) with total HP's around 45K.
As others have suggested this might not be the best camp for fingers since he's a bit of a pain with the adds but is manageable and was happy to take him out since he was up (and I needed a finger.) Dropped 6 fingers as others have also said.
I was able to then complete the Run to Daylight task with my merc with no issues. You'll just need to keep up a good pace to stay ahead of the re-pops. FYI, Ellery will follow the left path around the center pit when emerging out the door into the courtyard area. Once there, I used monk mez on the group of three gnolls and he was able to walk right past them to the exit. Just had to engage the gnoll at the zone in. You'll get the task update when he gets to the zone's cave entrance and then you report back to the fort to get your reward.