sounds like you first need something for bulk. make a cement paste using epoxy and bits of another solid material, such as old bricks or stone.

for the other issue where you can't get a nut on the backside, there are commercial products which use a plastic screen to form a plug on the backside of the wall material, which you can also improvise. (example: https://www.strongtie.com/screentubes_adhesiveanchoringaccessories/optimesh_screentube/p/opti-mesh-adhesive-anchoring-screen-tubes)