It was just conjecture on what I grew up around. They do go and verify the claim but most of the time they won't fault the farmers if the field is already reseeded after all they need to make sure the cover crop comes in good if the main crop failed. There's a lot of insurance fraud in agriculture mostly because the companies don't have the resources to go and check every farm. And to your final point they do correlate it to natural disasters, those events are rarely as catastrophic as they're reported though.