I hope he is a handy DIY type, cause he is looking at major expense if he needs a professional shop to fix that. It's not actually all that bad, but a lot of labor if you have to pay somebody $85-$100 per hour to do it.
Cut out and replace any damaged wood framing and paneling (inside and out), fit and glue on a new filon skin, and paint it to match. All the stuff can be bought online or locally.
Former owner of 2004 American Tradition
Home is in the Ocala Nat'l Forest near Ocala, FL