The errors in the Tom King book are minor - he's taken a story from another source and tried to simplify it but instead loses accuracy. For example, Henley originally told Cameron Crowe the story of Geffen in the sauna with Glenn, Jackson, JD and Ned Doheney but when King retells it, he puts Henley in the sauna, too.
In Mansion on the Hill by Fred Goodman, there's a good chapter on the Eagles and their management problems. The author interviewed Glenn Frey, JD Souther, Don Henley, Ned Doheney, Irving Azoff, John Hartmann, Harlan Goodman, John Boylan, Paul Ahearn and others in 1992/1993. i've seen bits of it in other books, but this is the clearest and fullest account.