I guess it was Bolton. Found this:
In July 2018, three months or so after becoming President Trump’s national security adviser, Bolton hired both Army Lt. Col. Alexander Vindman as a Ukraine policy specialist for the National Security Council and his identical twin brother, Army Lt. Col. Yevgeny Vindman, as deputy legal counsel in the NSC’s “ethics” office. Bolton is totally responsible for this pair of unusual hires. There is no explaining this strange duo of appointments as something that the bureaucracy simply slipped over on Bolton. That is not Bolton’s way.
Thanks for that info. I had just posted a question about that before I found your post.
Looks like Bolton was used as a pawn to further the corruption.
Wrong. Vindman was a holdover from the Obama Administration. Don’t believe everything you see on the internet