It sounds like Google views the information requested as not being necessary for certifying compliance and that they have supplied other information requested.
Do you know that they are in breach, or are you just assuming?
That's the whole reason the government is taking them to court: Google and the Labor Department have a disagreement and a judge will figure it out.
This is not how compliance works, you need to prove you are compliant not the otherway around.
OTOH, Google is essentially forced to take federal contracts, and cannot provide a reason that is acceptable to shareholders on why not.
Google isn't forced to take anyone's business. The small group of preferred shareholders still have total control over the company and have no obligation to explain their reasons to other shareholders.