Slide wall construction and damage question

Those skins are probably not Fiberglas as it will be glued to a lauan backer and remain fairly straight. the backer provider impact resistance. Many brands are using more durable plastics in these areas that don't need a backer. And the skin may only be secured around the edges on small panels like those, I.e. No adhesive securing the skin to the studs. Bottom line, while it looks bad, there may be no failure.