The fact that no one is claiming it doesn't mean it doesn't exist. For example, the FBI absolutely has the jurisdiction to investigate whether a federal judge has taken a bribe, because that is a federal crime. If you can come up with a crime here (and again, any attorney or agent with any motivation could do that), they can invoke jurisdiction.
The fact that they haven't is simply a reflection that (i) there's no "obvious" criminal theory here (the best I've heard is that the disclosure amounts to expropriation of government property, which is about as persuasive as it sounds), and (ii) the executive branch, to its credit, is recognizing that principles of comity and separation of powers are actually important and that it is therefore appropriate to keep one's powder dry for situations where there is a more conventional theory of a crime (rather than what is essentially an employment dispute).