More than that, he probably knows some of his underlings are trying to avoid prison and ratting him out to the investigation going on behind the scenes. Rosenstein and Mueller and Holder probably don't know what is going on, but they get info that something is going on. They are all probably scared S**tless because they know the death penalty could be in their dirty futures.
The DOJ isn't doing anything "behind the scenes" right now. They are part of the Deep State.
Read the Holder tweets. Holder is criticizing Nunes, Jordon, Meadows and a few others in Congress who are pressing the issue.
Holder is afraid of a contempt vote, that Trump will then fire Rosenstein, that the DOJ will then be cleaned out and that the Insurance Policy will be gone.
Only then will the prosecutions start.
Mueller, Rosenstein, and Holder were all involved in Uranium One.