I'd ask myself the question, "How would my book differ in any substantive way from a visit to JWSurvey or JWFacts?"
YouTube's Watchtower Examination series is among the best (let's call them tutorials) presentations for laying bare the dangers of Jehovah's Witnesses.
I've written and published 2 books myself.
In other words, unless you are a committed writer with a burning desire to say SOMETHING not already covered, I'd take your query to be an indication there may be better ways to be an activist.
How about 1st person interviews with DF'd ex-JW's as to the fairness of the process and the impact on themselves and their families?