EXCLUSIVE: A former charity executive who helped expose a questionable $500,000 donation to the Clinton Foundation is now being threatened by her old bosses with a lawsuit seeking tens of thousands of dollars, FoxNews.com has learned. Sue Veres Royal, former executive director at the Happy Hearts Fund, was initially quoted in a May 29 New York Times article that said the charity lured Bill Clinton to a 2014 gala only after offering a $500,000 donation to The Clinton Foundation. His office previously had turned down the charity's invitations, but this time he accepted; the accompanying donation amounted to almost a...