What happened as Noah watched the nalvage crew float the casino boat

Once they get on board the other boat, they find out he is their grandpa who disappeared a long time ago that they thought was dead. After that, Lieutenant Shucker accuses Noah's dad of arson. He says that the reason Noah's dad is wearing casts on his hands is because he burned his fingers. It is then they find out that Dusty's son Jasper was messing with cigarettes and accidentally set the boat on fire.