i believe that there are 3 people who know the absolute truth.  They are RJ, PJ, and........Crystal.  Halfway thru "White Lines", jane and the hottie are on their date.  She asks about his ring.  he says it is a long story and they better order drinks.  several minutes later, after an absolutely useless scene between fishcer and lisbon that was only their to show that there was a significant lapse in time, jane finishes telling her his story.  she then understands why he still wears his ring.

Now, if he told her that after several years of searching, he finally got his revenge and with it some long overdue closure, then her reaction would have been something like, "wow, so i guess now that it is all over you should consider taking it off and getting back out there".

instead, her reaction was to be understanding that he still wears it.  that would make sense if he had just told her that he just took down the BA, and another RJ accomplice, but he will continue to wear the ring until the day he knows for sure that RJ is dead.

i know for sure that the first thing i am looking at in S7ep1 is janes left hand.