And yet another diversion from shopping at a busy mall.
I managed to squeeze one more in a crowded area. This area seemed to be neglected but I found a fairly isolated spot for one more. You should be able to search without being observed by lots of muggles.
Finding this one is not too hard but retrieving the container may require a special tool or two. You will not need to open anything to find the container but you do need to be very observant for something "different" to find the container.
Fgerrg fvqr - fbzrguvat qvssrerag.