I just had my old bathtub/shower insert replaced with a tub insert and the walls tiled to the ceiling. When it was "finished" the grout line from the ceiling to the top of the tile is about 2 inches. I know this will not last, so my question is, now that I have paid for all of this, how can I go back behind them and make it right?
Don't pay them until they come back and do it right, but since you're asking I'm guessing you've paid already.
To fix, you'd need to get a wet saw or tile cutter and some of the tiles used in the project. Scrape out the grout, cut tile to 2" minus width of your grout lines minus 1/8" to 1/4". Put the tile up with mortar, grout, and caulk along the top where it meets the ceiling.