I believe that Carreyrou's book says Holmes built a relationship with George Shultz, then Henry Kissinger, William Perry, and Sam Nunn, through Stanford's Hoover Institution. They were all fellows at Hoover. I'm looking at page 181 in the hardcover edition. The book doesn't mention any family connections to Shultz. The military interest originally came from James Mattis, then head of US Central Command. The book says that Holmes met him "at the Marines' Memorial Club in San Francisco," but doesn't say more about that first meeting.