Clearly, there are reasons one might return to the WTS even after learning 'the truth about the Truth' and many of them have nothing to do with a resurrection of one's belief in the WTS. (As has been illustrated so eloquently here, it's pretty hard to go back to eating at a restaurant where you have proof that the staff spits in the food.)
Most common of reasons, of course, is family pressure and I've always thought that is totally understandable and a wholy legitimate reason.
Another reason might be a need for the effortless, automatic social acceptance provided by association with the JWs. I can't understand this in any other context than a failure to create a new social milieu for oneself upon exiting the JWs - nature abhors a vacuum. (Many possible reasons for this failure - insecurity, laziness, ignorance, lack of resourcefulness.)
Our friend SBF is in one of these predicaments, maybe both.