About your promise, that was under the deal of 1.5 courses released. If they break the deal, you are relieved of your promise.
This is exactly what you tell them. You don't have to be a diva or a squeaky wheel. You ask at the meeting, "Now the director gets a 1.5 course release, right?" When they say no, you answer "I am sorry that the administration is not committed to this project. I will not be directing the program."
For the love of all things holy, do not agree to do it for anything less, not even if they swear on a stack of Roberts Rules that things will change on down the road. If you do this even once, no one will get more course release for this task, ever. You may very well have to watch the initiative fail this time around.