More like a Rogue CEO and Board. Decisions of this magnitude going over so many years likely were made by the people at the top.
Recall that VW Chairman Ferdinand Piech resigned earlier this year http://uk.reuters.com/article/2015/04/25/uk-volkswagen-ceo-c...
The board was quoted: "The members of the steering committee came to a consensus that, in the light of the past weeks, the mutual trust necessary for successful cooperation was no longer there"
What likely happened was that the EPA filed suit against VW in April, and in uncovering the evidence needed to support the suit, VW chair Ferdinand knew that he needed to go in order to let VW continue to be a company. Or, Ferdinand could have been the ethical one and blew the whistle.
Either way, let out the stink. Corporations aren't nearly the kind of flawless entities you think they are.