Let me preface this by saying, I don't know if Mr. Cosby is guilty of all that he's being accused of. The number of women coming out against him is pretty damning, but no real proof has been offered (that I'm aware of anyway)
And it is this circumstantial, hearsay evidence that can actually play into the hands of someone trying to get a JW to grasp the seriousness of the child abuse claims in the JW religion.
Well, in my JW family, the standard reaction to the Cosby mess is one of acceptance of his guilt. Too many accusers, and too many tales from insiders for there to not be some truth to the accusations. They're saddened by it. He was a good TV dad, and seemed like a 'clean' stand up comedian that they could enjoy. But if the accusations are true, then, well, no more Cosby Show reruns, no more stand up records, no more live shows. He is no longer considered suitable entertainment.
Yet, when a (or if) a JW sees news reports and expose stores on child abuse within the WTS/JWs, they stick their head in the sand. Why not the same reaction as to the Cosby revelations? We know the answer to that, but if...IF...you could open dialogue with that JW, who gave up supporting Cosby, yet still defends the WTS, you can ask them to compare the situations.
"You no longer support Cosby, with no absolute proof even, but yet, when JWs are sentenced and imprisoned; when the WTS is found negligent, and ordered to pay millions, how can you continue to support an organization that IS guilty? Without evidence or a court case, you've judged Cosby, yet after many court cases, and judgments against JWs and the WTS leadership, you continue to defend them. How can you do that?"
Would it work? Who knows, depending on the level of cognitive dissonance. Yet, I saw a glimmer of light in one JWs eyes that made the connection. That one little doubt could lead to more doubts and questions. In time, with critical thinking skills, it could lead to a JW to judge the WTS guilty, and walk away from ever supporting them again.