You are going thru the horror stories on Samsung trade INS. On top of it you get to deal with Samsung customer support which sucks and FedEx customer support which isn't much better. We all cringe these stories and cross our fingers it isn't us it happens to. Even if you have pictures Samsung can say you could have filmed it or took pictures of it in the box but took it out after and sent empty box. I'm guessing that someone tried that in the past, lots of dishonest people in the country, sure Samsung has come across a lot of them.
Be polite and kiss butt for now, as someone else said if you do a dispute on the charge Samsung has video of the empty box so you probably will lose that. Good luck and keep us informed, hopefully Samsung will give you the credit.