Just thinking out loud here ....... if a razor is damaged because of inadequate packaging it will generally have a crack/cracks in the center, the area least supported, or at or near a third pin if one is present. The area around the wedge and pivot are relatively well supported for transport.

Looking at the photo of the cracks at the pivot brings to mind an inexperienced user stropping the razor holding it just behind the pivot, not at the tang. So that is one possibility.

It occurred to me, from my own experience, that you can telephone ebay. Find the 'contact us' tab, I think it is at the bottom of the page when you're signed in. A pop up will ask for an item # and you will get a number to call and have an hour or whatever it is to call them.

Give them a buzz and a heads up on what is happening. When you get the razor back you can better assess the damage and decide whether the buyer is trying to hornswagle you. Ebay will have been warned and it may give you more traction in getting things resolved in your favor.