It is unlikely that any insurance co will cover this type of damage from water intrusion. IMO, your issue was poor quality/bad design from the manufacturer. An example of comp coverage would be a tree falling on RV, or hail, wind blew it over, or even a tire blowing, which could do damage similar to yours.
Hope you get a few tips to repair from several of the regular rebuilders on this forum. JBarca comes to mind. You may try to send a PM to John for tips. He is a very friendly/helpful guy!
Jerry