Was General Flyn part of the swamp?
Flynn was fired from his position as director of DISA in 2014 because he crossed swords with the Obama administration, most notably with James Clapper.
Flynn also thought and wanted to investigate an Iran-Benghazi connection. Not exactly something that was a popular idea in the Obama administration.
In short, Flynn was viewed as a renegade who became increasingly unpopular in the DC Swamp.