Robbing the Stash
The guard will turn you away again and ask you to wait again, which just gives you more time for sabotage. One gentleman should walk up to you and mention that a key part for the Kayran trap is hidden in with Loredo's loot. It sounds like we've got another operation.
Wait a moment for Roche to talk to the guard protecting the entrance to the path. Once he walks past, move forward and get to the rock. Even though you don't have a blackjack, you can still stun guards with your fists. Wait at the rock until the guard turns around and starts to move back toward the entrance. You should be able to slip in behind him and knock him out.
Move forward to the corner and spy on the guard urinating on the wall. Apparently, he's set to respond if you knock over a bucket by the corner. Either give it a wide birth, or wait until he restarts the animation, to successfully get close enough to knock him out.
Climb the nearby wall to reach the back area of the barracks. That scene of Sile looking out the window is an important little clue. We need to get a little more intel. Wait by the wall and watch the two guards inside the yard. There's one guard at the back, and one a bit closer under the windows. You should be able to just round the corner and run up behind him as he walks out into the main yard for his patrol. The low wall by the exit should allow a similar takedown, which will clear the yard.
Now that you have some peace, you can walk back to the window and climb the ladder. Move up the crates and get below the window, then choose to look inside. You'll hear a decent part of Loredo's conversation, which will wrap up the majority of the quest.
The last step is to climb the wall by the main exit and get into the storage area. Move forward to the glowing chests to grab the iron frame for the Kayran trap, along with a design for a slightly better silver sword. Some have also reported good armor being inside this area. Regardless, take whatever you want and then climb the ladder in back to reach the wall. You can then jump off of the extended plank to get back into the yard and talk to Roche.
You'll eventually be able to get inside and talk to Loredo. He'll lay things out fairly well. He wants you to kill Ioverth for him, and clean up the area. There's a lot of money in it, and it's basically not that far off from what we planned to do. He also wants you to take out the Kayran, so it's probably a good thing that you got the trap. Either accept or reject his deal, then head outside.