T he real winner in the brouhaha over Brad Pitt’s appearing (wet, in his boxers) on the cover of Vanity Fair without the authorization of his publicist? Katharina Otto-Bernstein, whose documentary about avant-garde stage director Robert Wilson, Absolute Wilson, just opened (it’s only showing at two theaters). Wilson took the “video portrait” of Pitt. It ended up on the cover after writer Bob Colacello, who’d written a piece about Wilson, showed it to VF editor Graydon Carter. “We’ve had a long relationship with Vanity Fair,” laments Pitt’s publicist, Cindy Guagenti (she called Pitt’s lawyers). “And when they contact us for a photo shoot or an article, it’s always been on the up-and-up and we’ve been able to say, ‘No, we don’t want to do a cover this time.’ ” Though Pitt is promoting Babel, Guagenti feared “saturation.” In any case, Pitt’s not promoting Absolute Wilson. “I’d feel uncomfortable to push my film that I worked on for seven years and the biography that I also worked on for seven years through scandal,” insists Otto-Bernstein. Wilson says that he and Pitt “have a good relationship, so I don’t know what’s going on. This is all coming to me secondhand.” But Wilson’s manager, Charles Fabius, was excited: “We just got confirmed for a third week at Lincoln Plaza!” And that’s before a Today show booker called to get Wilson on.