To be fair, there is no real reason to be upset with the buyer as he may not have known the situation.

He could have just been a rando who jumped on a deal (if the house was large and included everything 65m is quite a deal, if not he kindda got ripped off anyway) and wanted to start fresh, which I wouldn't fault him for. But if you told him after the fact what happened, should he take a 65m hit to restore your fc? No, imo.

I would focus on the seller in my reports unless you know for an absolute fact that the new buyer was knowingly screwing you guys over pre-purchase.