I've heard of a novel being written in 2 weeks (Halo: The Fall of Reach), but that doesn't include the time it takes to edit and format the book.

Let's not forget the amount of time it should take to do actual "research" for a book like this, providing it simply wasn't vomited out beforehand. And according to searches, the Maui fire started on the 8th or so of THIS month. 8 days for this book to be written and published? Even with on-demand publishing, that's a stretch unless they had it done in advance.

Even if it was written with AI, things are still ongoing as far as how long it would take to do "research" about what happened.