Until it's proven otherwise, I'm going to assume that these guys are the same ones that did the hack and that the North Korea link is bullshit.
So you're going with "no evidence" to support your conclusions over "some evidence". Yep, that's some sound reasoning there. Look, I have my doubts about the Norks' ability to pull this off on their own, but then again, that is a part of the world where governments (not beholden to Wall Street and priorities that rarely stretch beyond the current fiscal year) are willing to play long-ball. They may well have been auditioning players and laying plans for a long time, or they may have outsourced the work. In any case, we have some evidence implicating the Norks in an action that is entirely in keeping with their global "character". Guilty until proven otherwise.