First off, sorry to hear about the damaged card, that's very unfortunate. But you've never actually held the card in hand yourself, personally if I'm going to make accusations towards someone I would need to be 99.9% sure that that party damaged the card. The only person I would trust is me and my own two eyes.
The card was bought off eBay from a seller with only two feedback and with a small photo from a camera phone. I've purchased cards before where the seller said the card was mint, only to find out the card either had scratches, a bent corner, a crease, or a card stock split. I only noticed the damage by having the card in hand and by taking it out of the holder and viewing it at different angles. In each case I was upset and returned the card to the seller for a full refund, because I personally had the card in my hands and was able to assess the condition. I'm not saying the card was already creased from the seller, but I am saying that it is a possibility. Sellers don't always disclose the correct condition, I don't care if the seller has 2 feedback or 20,000 feedback, it happens all the time either purposely or unknowingly.
I don't doubt that you trust this friend of yours whom you've never met, but he may have accidentally damaged it. Maybe when taking it out of the holder for examination or unknowingly when packing it for shipment. I'm not saying that the damage happened while in your friend's possession, but I am saying it is a possibility.
And I'm not saying Beckett is innocent, because it is also a possibility that they creased the card. But, I think the chances that it may have been damaged prior to them receiving the package are just as great.
Without actually having the card in my own two hands and looking at it with my own two eyes, it would be hard for me to put the blame on one party and know for sure when the damage occurred.
Again, sorry about the entire situation, especially since it's such an epic card.