DING DING DING!!!! We have a winner!!!! I walked in there after a ride on Ariel and there is all this woodworking stuff just to the right of the DVC dude (who was super friendly without any attempt at sales). The sign out front says, "H. Goff Cartography," thus the map clue. I know I am not nearly as cryptic as you Jeff or Justin. Here is a sign that was just outside as well.
Guess that means I can't use this as the next WAI... Used the booth for shelter from the rain on my last trip, but did not see the "artifacts".