Oh, I believe that those documents no longer exist, but they were "lost" in the same way that I happened to "lose" my virginity as a teen-age boy.
The FBI has no credibility. Any. At all. Zero credibility. It is a garbage institution run by Democrats for the benefit of Democrats, and it's been exposed as such. Burn it down. You can't trust the FBI to follow their own procedures, and that means you cannot trust them to investigate anything or anyone. Any investigation they conduct has to be considered either a political operation or the fruit of the poisoned tree.
Given how every single Democrat connected FBI person has skated on the multiple crimes they committed, there is absolutely zero chance that anyone will actually be punished for their "failures", which is to say their deliberate actions undertaken to cover up the larger crimes they committed in service to the Democrat party.
Trump's election has ripped the curtain away from the corruption at every single Washington D.C. institution. There's not a single that's headquartered within Washington D.C. that I would trust, because they have all shown themselves to be partisan political Democrat agents. They serve their socialist masters, not you, not America.