I suspect Zayat wanted Baffert to talk to the Earnhardts to pump up Zensational's book, but I doubt he would push them into a stallion unless he was genuinely enthusiastic about the horse. He could always have gone back to Zayat with spread hands, saying "I did what I could, but they're set on Curlin."
(But I think Curlin would have been a better choice
)