Same thing happened to ours, same model year, and we replaced the whole roof. Homeowners insurance paid for it but with a $1000 deductible. I wish now I hadn't spent the money, should have just silicone caulked the hole and put Durabond over it, would have held just fine. Other owners told me they did that and it worked fine for years.
p.s. I think the product name is Durabond but maybe I'm wrong; it's a waterproof, flexible and very sticky tape. Available at all RV dealers and stores. Someone else can verify the correct name I'm sure.