Don' forget, she's been around an absolute genius at parsing for the last few decades.
I Haven't Been Interviewed by FBI on Email.
Probably true. They're more interested in the corruption aspects anyway, that takes priority.
Though if I were running the investigation, I'd get my ducks in a row, THEN interview her. More than likely after arresting her. Lean on the small fry first is a time honored tactic because it works.