My guess is they are "pertinent" based on (1) who the emails were to/from, and (2) the dates they were sent. "Pertinent" is not synonymous with "incriminating." Likewise, it doesn't preclude them from being incriminating.
For example, if the data shows these e-mails occurred within the same timeframe as the 30,000+ emails that Hills and co. deleted, they are newly discovered evidence that the Feebs weren't privy to the first go-round. That would certainly make them "pertinent" without having to examine them for content. In that scenario, they were made "pertinent" by Hills attempts to hide them from everyone.
Throwing political allegiances out the window for a moment, common sense tells you that someone doesn't go to all the trouble Hills did to hide/destroy these emails unless there was something in or on them that could hurt her. Surely even you would admit that?