That makes religious sense. Christians who pray for the souls of the departed know that it is useless to pry for those in Hell as there is no redemption for the damned. For a Moslem those who die unconverted are in Hell.
Those bombers, I don't know what God will do with them. I can't bring myself to pray for them unless it's a person who was forced to do it which there have been some, a ten-year-old in Africa the other day. In such a case, it would be the fault of the person(s) who forced them to do it.