Oprah is worried that someone might decide to go for some really deep pockets and sue the pants off her for making this book a best seller. Were I the doctors and rehab center in MN that this lying author maligned, I'd hire a really good lawyer and clean out Oprah's prodigious bank account. She's fortunate that her audience is a cult of ignoramuses who would never conceive of questioning her judgement.
2) The article is right, in that publishers accepting what authors give them as "true" is nothing new. In the 1970s, Robert Maddox published "The New Left and the Origins of the Cold War," in which he exposed massive fraud in six or seven "New Left" history books that were widely heralded when they came out (such things as using ellipses to join together different speeches from different days!) But Maddox's greater revelation was that the publishers and REFEREES didn't bother to check this stuff.
This whole thing was repeated with Bellisiles' idiotic book on guns ("Arming America") where, again, the publishers didn't bother to check citations . . . NOR DID REFEREES.
This is becoming a huge problem in both fiction/non-fiction trade publishing and in "academic" publishing.