Like what? I'm not a lawyer, but I can only think that if they have any intelligence assets that were about to get slapped with charges, they can whisk them out before the alphabet soup boys come and round them up.
They could go to anyone important who is under investigation/has been indicted but doesn’t know it yet, tell them, then have them do things (data dump from your employer, etc) in exchange for help fleeing the US to Russia.
Russians aren’t dumb: it would be absurd to think they’re not doing it, right now.
Blackmail. Virtually all sealed court records are sealed because someone would be harmed if revealed. How many elected officials are out there with sealed depositions alleging sexual assault, etc...?
"Like what?"
Like the article mentioned "informant names" seems pretty nuts.