I read the same book, in 2018 but find it unforgivable that you left out one of the juiciest stories in the book.
This was about a Naval officer who fronted a deal from a Lebanese owned company, made a presentation to GEJ, who was smart enough to call Ngozi Okonjo Iweala to the meeting. Part of the terms of the deal was that the government will provide a 2 billion dollar guarantee to this Lebanese racket.
It was at this point that our protagonist began to ask penetrating questions which led to the entire pitch collapsing. Had Ngozi not been at the meeting, Nigeria would have been scammed by a bunch of foreigners.
There isn’t a reading culture for if there was one, The Nigerian political class will have been defenestrated by now.