In the episode, one of the Scientologists yelled, "I'll sue you in England!" at the end. I didn't get the reference (if there was one). Perhaps that has something to do with the decision.
Assuming it wasn't just a throw away line then it's probably a veiled reference to the differences with British copyright laws. In England you can copyright facts, in America you can only copyright the presentation of facts, thus the give away of all the "secret" beliefs on Scientology is probably much more suable in England than it is in America (depending on what Scientology has published in England of course).
When Liberace took the stand, Beyfus (his barrister) asked: "Are you a homosexual?" Liberace: "No, sir." Had he ever indulged in homosexual practices? "No, sir, never in my life ... I am against the practice because it offends convention and it offends society."If Liberace can be legally not-gay in England, Tom'd have a good chance of winning too
England is notorious for having lax libel and slander laws. Cruise's case would be thrown out in the US, but he'd probably win in the UK. Celebrities sue over there all the time. Frequently US celebrities will look for any reason they can sue in Britain.
From what I remember from a McDonald's case, in suts for libel or slander in the UK everything is heavily weighted towards the plaintiff. Guilt is essentially assumed once the plaintiff shows the offending material, and the defendent has to prove he's innocent. Scientology even attacks distributors, such as when they forced Amazon to drop an anti-scientology book.