Had this twice at Godaddy! Both sales were cancelled by Escrow.
As both sales were quite big, I contacted Escrow, but they couldn't help as the buyer never logged in at Escrow to give their details.
I also called my rep at Godaddy, but she couldn't give me any details, not even a hint (with the second sale I had a hint which company it was) out of confidentiality, even after I explained that Sedo gives the details of a non-paying buyer.