Smoke bombs won't do any damage to the structure, but will force the people to flee. Israel should announce repeatedly and loudly that they are going to fill the church with smoke and that the people in the church should get out and enter one of the buses that will be lined up in front of the exits when they do. Anyone who leaves the church with a weapon in hand will be shot by snipers. Anyone who leaves the church and doesn't enter a bus will be shot by snipers. When the smoke clears, IDF troops will enter the church and shoot anyone still remaining inside.
This one is too easy to resolve. Why all the diplomatic wrangling over it?