Who is Chuck McKee from See No Evil: The True Story of a Ground Soldier in the CIA's War on Terrorism and what is their importance?

Chuck McKee was one of Robert's colleagues in Beirut, Lebanon. When Robert was reassigned to Paris, Chuck was reassigned to Beirut. Robert jokingly warned Chuck to get himself out of Beirut before the terrorists got to him. Six months later, Chuck was killed in a terrorist attack when Pan Am 103 exploded over Lockerbie, Scotland.