This is a legal contortion apparently created by a leftist judge just to protect Comey and people like him. It can be revealed to journos – if needed to protect them – and no court can second-guess that judgment. This is unreasonably broad and I hope it can be appealed successfully to the Circuit or if necessary to the Supremes.
Failing that, as noted in the comments to that article on mcclatchy, it can fall entirely within the President's authority. In other words, military tribunals. The civil system is forcing the tribunals, and they may get them.