Nick - I agree that truth is not her first priority. I think her first priority is the idea of unity and loyalty to the group. When I told her that the book was written by a man who was not only a GB member but also played a key role in developing the JW encyclopedia "Aid to Bible Understanding" that became the two-volume set that she looks things up in, "Insight on the Scriptures," she said there were teachers in the 1st Century who taught the "truth" at first but strayed from the organization. She said Paul warns to stay away from them, and do not pay attention to what they say. She assumes the book is just muckraking, stirring up trouble, bad energy, and causing divisions, even if it is written by someone who used to be at the top level of the hierarchy. As you pointed out, at the end of the day, she wants to blindly accept what she is told to believe because she feels loyalty to this particular group is her first priority. They did something to gain her trust, and I don't know what it is.
She even said, "even if they're wrong, I would still want to be part of this organization." I wonder if your wife feels this way. When I point out that she is being loyal to an organization, she says no, not really, because her loyalty is really to the Bible. She feels that the org is following the Bible more closely than any other org, even if they are wrong in some aspects. If I point out problems with their Bible interpretation, she says she will trust their interpretation and wait for them to clear it up. She has somehow become convinced that this group is more sincere in their efforts to understand and follow the Bible than anyone else. Maybe it's their supposed "sincerity" that binds her to them.
My study conductor's wife illustrated it like a marriage. She said if you are a loyal wife, you are going to remain tied to your husband even if he has made and still makes mistakes. You are also not going to read disparaging material about him, even if it is true. She said the relationship between a baptized JW and the org is kind of like that.