James Baker, former FBI General Counsel, is the only witness against Sussmann.
There are no documents, no audio, and no contemporaneous notes.
James Baker is now employed by Twitter.
Baker has stated publicly that - after five years - he no longer has a clear memory of his conversation with Sussmann.
https://technofog.substack.com/p/where-does-john-durham-go-from-here
“According to Special Counsel John Durham, Sussmann would repeat this lie on February 9, 2017 to two employees of another government agency (“Agency-2” in the indictment; possibly CIA).”