Occam’s Razor would lead one to think that a raid (involuntary production of evidence) on a whistle-blower would only be done to discredit the person who voluntarily came forward, or punish the person for simply stepping forward.
On a similar FR thread a poster said that this raid could be a standard check to see if a whistleblower has submitted cherry picked evidence, discarding exonerating material. Seems to me that there would be a better way to investigate such concerns.