To my understanding, creators can pull their items from the Marketplace, and they are no longer available for purchase, but they are still supposed to be unlocked on the accounts of those who already purchased them in the past. I have considered taking a few of my eldest sets down in the past (and still kind of want to) but I have tried to avoid the confusion and risk of error in the event something happens and someone lost content they paid money for. I hope you can get everything sorted out! I am sure if you contact Roll20 Help Center they will do everything they can to help you out.