This tells me that the FBI crashed the computer.
Or that various agency heads, including Lois, figured out that the FBI could access their email , email logs, etc. without getting a warrant first.
That wouldn’t give them time to cover up or get rid of evidence.
My guess is that all incriminating conversations were done personally, or via ‘blackberry’ (remember, all top execs got one) using alias email accounts AFTER that point.
This focus on her ‘missing’ emails is a wild goose chase. Any ‘missing’ emails produced will have nothing incriminating on them, further justifying Lois’s claim of innocence.
The POINT is to keep us busy looking for it.