I've done this once before using a modified latex thin-set mortar, but it fell off again yesterday (about 2yrs later). I've decided to use either a construction adhesive or epoxy to re-mount the soap dish back to the wall...as you can see from the pictures, the thin-set is still in the wall and there isn't much room for much product.
My question is, which product will work best in this application, construction adhesive (liquid nails, loctite power grab etc. or epoxy, i.e. jb weld).
I will be using 100% silicone to seal around the soap dish once it is re-fastened to the shower wall.