Fiona Hill was recruited by Flynn
https://www.defenseone.com/ideas/2019/11/some-you-committee-appear-believe-russia-didnt-meddle-2016/161478/
From 2017 until July, Fiona Hill was senior director for European and Russian affairs on the National Security Council. This is part of her opening statement in testimony to the House intelligence committee on Nov. 21, 2019.
For the better part of three decades, I have built a career as a nonpartisan, nonpolitical national security professional focusing on Europe and Eurasia and especially the former Soviet Union. I have served our country under three presidents: in my most recent capacity under President Trump, as well as in my former position of National Intelligence Officer for Russia and Eurasia under Presidents George W. Bush and Barack Obama. In that role, I was the Intelligence Community’s senior expert on Russia and the former Soviet republics, including Ukraine.
It was because of my background and experience that I was asked to join the National Security Council in 2017. At the NSC, Russia was a part of my portfolio, but I was also responsible for coordinating U.S. policy for all of Western Europe, all of Eastern Europe (including Ukraine) and Turkey, along with NATO and the European Union. I was hired initially by General Michael Flynn, K.T. McFarland, and General Keith Kellogg, but then started work in April 2017 when General McMaster was the National Security Advisor.