But the GAO has to make its findings public, or at least put it in congressional review reports. Congress persons are political animals by nature, both parties, and if they can take something out of context or cherry-pick bits and re-package them into a scary-sounding narrative to score political points, they will.
Look how they mangled issues with emails, back-up systems, file formats, servers, hard-drive failure rates, etc. in the Lerner/IRS situation. (Granted, some of the mangling of IT concerns* may have been sheer ignorance instead of intentional political manipulation.)
Transparency is a double-edge sword. I'm not choosing sides here, only saying that they are probably between a rock and a hard-place.
* They probably also mangled non-IT subjects, such as law, but I don't know enough about those topics to readily spot mistaken notions or claims.