As the poster said above, this guy is stealthed. You won't see him until you're practically right on top of him, and he shoots you. He is yellow to a level 12, but a fairly easy kill. Hes about 1/3 of the way up the wall.
Received the Quest "Traitorous Intentions" from the Darkwood Defector standing on the steps in the caves NW of the Ship's Room. Looked for the Darkwood Scout and was unable to find him. Started running along the north wall of the Ships room (still did not see him), but suddenly I had an arrow in me. I turned to see him not quite halfway up the wall at loc #24458, 12950. Don't know, since he is a Scout, if he was stealth and I missed him OR he spawns when the person with the quest is in the area.