It isn't just government officials who can be imprisoned for leaking the names of indercover officials:
"Disclosure of information by persons who learn identity of covert agents as result of having access to classified information
Whoever, as a result of having authorized access to classified information, learns the identify of a covert agent and intentionally discloses any information identifying such covert agent to any individual not authorized to receive classified information, knowing
that the information disclosed so identifies such covert agent and that the United States is taking affirmative measures to conceal such covert agent's intelligence relationship to the United States, shall be fined
not more than $25,000 or imprisoned not more than five years, or both."
(see the link about the Identities Act)
Did Novak have any authorized access to such classified info? If not, this particular statute seems not to apply.
>>knowing that the information disclosed so identifies such covert agent and that the United States is taking affirmative measures to conceal such covert agent's intelligence relationship to the United States,<<
Key part of the statute. No crime was committed, and even if there technically was a crime committed, Novak is protected by the First Amendment, as is any non-governmental official who isn't under some duty of non-disclosure.