I suspect grey. He does have his signature on several FISA court documents to spy on Trump.  If he knew the dossier was fake, and I believe he did, then he lied to a federal judge, and a federal court.  I don't know how the law works in his case, but I know if I did that, I'd have plenty of time to read up on it. At some point, RR must have known the jig was up, and the only way to save his skin was to cooperate with POTUS in exposing DS operatives inside the DOJ. But I agree with your assessment - there's going to be surprises.    https://dailycaller.com/2018/01/29/rod-rosenstein-renewed-spy-warrant-against-trump-adviser-last-year-report/