It must be a Jesuit school, otherwise the topics would not have been allowed. For fifteen, the young man has a fairly sophisticated and mature take on things, but he also grew-up in the school of hard knocks...
A little more research would have put a finer spin on why God allows terrible things to happen, but in the end it is unexplainable just as the teen concluded. Catholics do have a sharper sense of guilt than some religions, but there are plenty of non-catholics with problems with guilt, some overwhelmingly so.
A provocative story, but perhaps it makes the idea it is okay to dismiss the faith of others reasonable, when faith is often the opposite of reasonable.