it's my old (and unwavering) theory that Rubel is actually the REAL-TRUE LEADER OF THE ORGANIZATION further additionally supported by chapter 107 now as well!
(like how in Batman Begins, Raz al' Ghoul, pretended to be a subordinate, when he was actually the real-true leader of the league of shadows, and not that other puppet-leader-decoy guy. Rimuto might be a similar puppet-leader-decoy guy for Rubel...)
hehe.
The only mentioning of Rubel being a "spy" for this supposed "other side" came right out of from Rubel's very own (lying?) lips !!!!