Don and crew were probably pawns in that alleged scheme, if they contributed at all.
I disagree though that the goal of the Trump crew was to "damage Hillary". The Clintons and Trumps have been friends for decades. I believe what is most probable is that every action at the top was to elevate the drama, turning the election into a sort of WWF match for another season of the apprentice or whatever. To support this theory, I give you the Birther drama and Don taking credit for the release. To his credit, It was comical and entertaining, but it was an obvious PR stunt.
The actions of the underlings is the result of good old fashioned greed. Occam's razor and such.