Flat Panel Caravans are becoming very popular in Australia. When they get damaged the best approach is to replace the complete wall unless the damage is minor. These walls will become more popular in time.
Recently we have replaced damaged walls on a Jayco Silverline and a Avan Aliner. Jayco and Avan are currently the most popular brands with these walls. Done properly a repair such as this has no detriment to your caravan sealing or construction.