Hopes to save them by having them help clean up the place? BS! If they are underage, sue their parents ang restore the house, plus get back personal items or their value. Tough love is what they need not a motivational speech.
This. Since he's a motivational speaker, he probably feels compelled to take the "let's give them a second chance and put them on the right track" approach.
If he doesn't want them to get thrown in jail, fine by me. But I would make those who have the courage to come forward clean it up and then work to pay off the damages in full. For those who don't come forward, I would hunt those down and make sure they are prosecuted.