Searching The Secret Stash

After discovering a loose brick and a hidden note on the prison wall behind the porch where you talked to Jacques, read the mysterious missive, and set off searching for a hammer and chisel to stash in the wall.

You don’t have to go far to find these two items; they are on the small cart under the gallows just to the left of the porch. Procure both the hammer and chisel, return to the loose brick in the wall, and place the items in there. Now you must wait. Simply continue with the Main Quest until this Secondary Quest updates—or meditate for two days.