From their website:
"For cancellations less than 48 hours before check-in, deposit will be forfeited."
Sorry, no PR nightmare here. Rules are rules and ANYONE can call and say they got hurt, sick or whatever and try to get their money back. You truly don't have a leg to stand on and I just don't get why you think you should be exempt. It's up to YOU to ASK what the cancellation policy is and to decide whether or not you like it. Campgrounds aren't charities-they are businesses.
BTW, whether or not you know if you can make it by 11/16, I would accept their offer and then go if able. At that point you might be able to negotiate into next year.