The ruling is not based on the merits -- whether Christie knowingly or unknowingly sold wine of a dubious provenance -- but simply that Koch waited too long to file his case.
He bought the wine in 1987 and 1988. A widely publicized investigation in 2000 revealed suspicions about the wine's actual origins. Yet Koch waited until 2005 to act on any suspicions. He may have prevailed in court had he not delayed. By waiting so long, he lost the right to sue.
My father is good friends with Bill and has had several discussions with him on the subject, so I may be a bit biased. I also read Billionaire's Vinegar. I believe that Christie's did not do the due diligence and that Michael Broadbent was enamored with the fame and money stream that Rodenstock represented and therefor took for granted things he should not have. I believe that the court ruling actually claimed that Bill should have filed suit sooner.
To Bill it's not about the money (he certainly has spent much more to pursue the perpetrators of the fraud than he ever did on the wine), but about the principles of honesty and integrity.
Too bad. Buyer beware.