It wasn't all for nothing as he died after the recruitment mission (I was hoping for a prove your worth mission as those are much easier) but all his recruits died along with him (that happened because I ran away to take out a captain that I issued a death threat because of course the power struggle managed to bring him and three bodyguards there) so I did get the "No Power in Numbers" achievement.
I think what makes the stealth missions so frustrating is the fact hat there's no immediate replay as there's NO checkpoints. Who thought that was a good idea? "Hey, let's have them go to jump over a group of obstacles to get across some uruks but then have him fall in the middle of them to make him abandon the mission and run back to the mission start point." -_-