My take-away from this is that the indexes and annotations may be subject to copyright by the private party that wrote them-- but from my experience working as a VA employer on policy and procedure manuals, with some indirect experience in handling material that was produced by contract workers, this would depend on the wording of the contract between the government and the private party. In most of those contracts the author is hired as an agent of the government and his relationship to his product is the same as that of any government worker to their assigned tasks, which means he cannot claim copyright and the work is in the public domain. There are major benefits to being an agent of the government and that is usually how this kind of thing is done.
That said, I don't see how Georgia could win this lawsuit, since if the material is copyrightable, the author, and not Georgia, would hold copyright and Georgia would have no standing in the matter. If the author was working as an agent of Georgia, then the work produced is in the public domain, and there is no valid copyright.
In either case the suit seems like a frivolous one, since if there is any copyright involved, Georgia cannot be the party that owns it.
Of course the defending party would be facing legal expenses to just get the case dismissed, and Georgia might be using that as a club to get an early out-of-court settlement. There is a term for legal battery but I don't recall it (coming up on my 10th year of retirement), and that is what Georgia might be attempting with this. Filing suit, even when you know that you cannot win in court but you think you could get an early out of court settlement, should be considered a breach of a lawyer's duty as an officer of the court. Lawyers who do this should be penalized, and in some cases disbarred. But that doesn't happen. That part of the legal system is totally broken.