Disney would not have any legal authority to "force" a buyer or seller to follow through with the contract once they waive. The only legal edge that Disney has during the resale process is the ability to step in as a buyer to complete a transaction. Once they waive their "ROFR" the completion of the sale is up to the buyer and seller. If one backs out after that point it would become a civil issue between the two parties.. I know when I first started my resale purchase I signed a contract.. This initial signing was not notarized or anything like that, but still a contract stating that I was purchasing. So if a buyer backs out at the end (or a seller) I could see a civil suit being filed, although, not sure how far that would go...