Apple is "involved" in the same way that the city government is "involved" when someone steals your car and drives off down the street with it.
I sympathize with your son's situation, but starting out with "Apple involved." just makes me think your initial interest is seeing how much you could sue Apple for because some developer released a clone of your son's game. App cloning happens all the time. It sucks, but it's no more Apple's responsibility than it is that the city didn't stop the car thief from driving off with your car.
The developer is apparently UK based, so if there's any way you think they could have seen your son's game and cloned it in a month, you're free to complain to Apple and see if they'll pull the game, but beyond that I don't think they have any responsibility to help you at all.
I'm sorry for your son's rapid experience to learn that there are people out there who clone apps to make money off of someone's work. He should go have lunch with Dong Nguyen and Gabrielle Cirulli, they'll have something to chat about.
BTW, if you're on the "lawyer up" warpath, don't forget Google too for another fat purse to poke at. No Brakes is in the Play store as well.