If you can sue someone for expressing their truly held opinion especially when that person doesn't have a fiduciary responsibility, then you can sue anyone for saying just about anything. You could sue anti-vaccinators, including President Trump because you chose not to get your kid vaccinated and then they got sick. You chose to listen to someone while not listening to the advice of your child's doctor. Something with the Blood Issue, if your doctor decides that they recommend a blood transfusion you can choose whose advice you want to apply. And yes you might feel that Watchtower has so much control over someone but that doesn't mean that you can sue over it. Even as the paper indicated that saying that people who want to give you a transfusion is from Satan.
Even in the Unitarian case that is the major basis of the article the court wrote.
[21] Leal contends she was falsely imprisoned by the Church at Boonville, at Camp K, at Boulder, at Los Angeles, and at various locations in San Francisco. fn. 16 She admits she was theoretically free to depart at any time; she was not physically restrained, subjected to threats of physical force, or subjectively afraid of physical force. She insists, however, that her "imprisonment arose from the harm she came to believe would result if she left the community." That harm, specifically, was that her family "would be damned in Hell forever and they would forever feel sorry for having blown their one chance to unite with the Messiah and make it to Heaven."
The claim cannot survive constitutional scrutiny. Although Leal correctly asserts that false imprisonment may be "effected by ... fraud or deceit" (Pen. Code, § 237), her theory implicates the Church's beliefs: it plainly seeks to make the Church liable for threatening divine retribution. As we stated earlier, such threats are protected religious speech (see Fowler v. [46 Cal.3d 1124] Rhode Island, supra, 345 U.S. at p. 70 [97 L.Ed. at p. 831]; Van Schaick v. Church of Scientology of Cal., Inc., supra, 535 F.Supp. at p. 1139) and cannot provide the basis for tort liability. Accordingly, we hold the Court of Appeal correctly affirmed the summary judgment for the Church as to Leal's action for false imprisonment.