It is impossible to make someone use their critical thinking if they refuse to do so. I worked with a guy who I not only grew up with but we were good friends. We became partners in business. I started to become awake in the 80s and started in the early 90s to say if they change what a "generation" is then I am out. In 95 when the changed the definition of the word,I threw down the watchtower mag and said I am done. I would talk to him about 607 BCE, all the wrong predictions and even had parts of the crisis of conscience I would read to him. The only time he ever walked away was if there was a chance someone would hear. If we were in the van driving to the next job he would talk all day. Once in a Library when the internet was new I looked up Randy Waters site and he walked away looking around. Once I said that the JWs were like the Scientologists to an elder and that elder went off the rails and tried to get to repeat it in front of two elders, then my partner left the business and would not talk to me. I had went too far and he was afraid for his reputation in the cult.
I learned that you can not make someone think. My Grandfather was a CO for years, Special Pioneer for many years and elder for what seemed like ever. He would talk to me in private and admit he knew about 607 for years and that the society was wrong on many points but it was still a good way to live. Many are not in it because they believe but that their social life is built on it.