I saw you mentioned something about glue, I own land hermit crabs at times people want to glue things down to make second levels for climbing they use aquaium "glue" or you know the stuff that they use that holds the sides together. If they use that in aquariums why can't you use it on your decorations? I use the plastic mat that people buy in the craft section to make hook rugs, comes in all sizes and is dirt cheap and cuts easy & mount on the side of my tank for my crabs to climb on. I paid .97 for i think a 12 x 12' square of it. just an idea to use to cover your hole,and it's small enough the frog can't get any bod part stuck in it either.