I can now confirm, having just spoken to him , that he DID tell them that that was the deal and that they were responsible for telling their groups. He just told me also that, not only did they not buy anything, but they never thanked him or his staff either. He also confirmed that it won't be happening again unless the committee arrange it.
I reiterate that so many people in folk music are tight-fisted. It's not always about lack of cash, it's often about lack of respect.