According to Wikipedia, Mike Rinder is 54 years old. As long as he still believed in what he was doing in the CofS, running OSA and being an international spokesperson and all that, I expect he felt he had a meaningful and successful life going. If Scientology is still good and it's just the Church that's bad, then he still has a good shot at salvaging that meaning and success.
If it's all just an evil scam, he's got nothing, and he's suddenly looking at starting from way back down at the bottom of the hill of life, in his mid fifties, with his life's only major assets all turned into nasty liabilities. If he had gotten used to thinking of himself as the hero of his own life story, now suddenly he would have to re-identify his role as victim, at best. That's got to be a tough pill to swallow. The temptation to accept some blame, but insist that the cause is salvageable, must be enormous.
I don't really believe in a personal devil at all, but if I can use the idea of a tempter as a personification of temptation, I think the devil is always telling us that we haven't yet crossed the lines that we really have crossed, and also telling us we've already crossed lines, when we really haven't yet. 54 may seem too late to start afresh to make something of your life, but it's really not. It won't be the same kind of something you can make starting at 17. It can be a rare and valuable variant form of meaningful life. I hope Rinder can find a way to do this.