My question to smooth and other Monero developers is, "Has BCX revealed any exploit to any of you?", because the posts I've read from smooth seem to be wordsmithed in such a way as to avoid definitively answering that question.
No. You are reading into wordsmithing that doesn't exist.
rpietilla may not be part of the core team but he is heavily vested and has personal ties to someone that is. As such he has access to insider information and is able to use that information to his advantage. He might as well be considered part of the team.
Who is the person he has personal ties to?
I don't know what "personal ties" refers to exactly, but he certainly is friendly with several of the developers and I think David was going to be staying at his castle for a while. I'm not sure if that is still the plan, but regardless it has nothing to do with Risto's relationship to the project or (non) position in it.
But the part about "insider information" and "might as well be considered part of the team" is complete bullshit.