I have to fix a hole in a shower tile wall. By accident, the tile wall was pushed in where it meets the tub. Four tiles were pushed about 4 inches into the wall, and after pulling them out, I discovered that the plaster board behind is broken out-about 10" x 10". None of the tiles are broken but there is not anything behind the tile there now but insulation so I don't know how to reattach the tiles that have come out. Please help! Thanks!!!