No problem, Mark. I’m talking with some folks and hope to find someone soon but until I have a bird in hand I keep inviting those in the bush too! You can contact Pork Belly Ventures about a rider wristband if you cannot find one on your own. They have customers who need to drop out and others who are on their waiting list to get in but they say that every year they have more sellers than buyers so you should be able to get a rider wristband from them.
Unfortunately for you, Mark and Karen, most of their customers were planning to use them as a charter and therefore would not have vehicle passes to sell. Some of their customers use only their shuttle bus service from end town to start town and while it is a lot less likely, some of them might have vehicle passes to sell too. You can ask, they are nice folks who will help you and their customers with passes to sell if they can.
I will try to get back to you both to see where you are if this should happen but my “nuclear option” for this year is to bag the motorhome, sell the passes, and go with a charter or the Register baggage trucks. That is NOT my plan at the moment but life is life and plans change.