A couple weeks ago as I was coming up the unnamed trail from the Villa Maria area, I noticed a little side trail and decided to explore it. It leads to a fairly big plateau overlooking the former quarry and the Deep Cliff golf course, and at the far end there's a large pine tree, surprisingly with a tree swing attached. Follow the trail between the swing and the rim for just a short while til you see a faint spur off to the left just after 2 small toyon plants.
You are looking/feeling for a black bison tube, hanging from a nail on the top of the branch indicated by the top arrow in the gallery picture, about 2 inches out from the trunk. The branch is the top-most, rightward branch in the picture, which was taken standing with the tree between the canyon and me. The tree is the one with the swing on the other side. You can reach the container when standing on the lower marked branch in the picture, or if you're a lot shorter than 5' 10" you might need to climb up a little bit further.
I'd recommend taking the container off the nail and climbing back down to the ground before attempting to sign the log. Please replace it on the nail positioned such that it's not visible from the ground. Please be stealthy to minimize chances of it getting muggled again, and be careful!
Congrats to penguinphloppers on the FTF, which he deserved after just missing the chance to put one of his JAS caches in this area.
Update 6/27/20 It's back in the tree, but now it's a small bison tube invisible from the ground.
Update 4/11/20 Unfortunately the fun tree climb hide proved to be too muggly so I had to change to a more typical hide. Coordinates updated.