If I wanted to ‘sell’ such a clouded entity, I’d just 100 lease it. As in everything else a market would/is develops and they would like any lower rated product be moved at that price. You could also rent it. ( Off the cuff, I’d say half of Latin and South American land is lived, rented, sold without title, and with out courts.
Further, you have to look into the incentives of the courts, lawyers for and against. None have much interest in clearing this. They made money selling, now filing claims, and their brethren defending. Lawyers and judges have to eat too.
I do quite a bit of bankruptcy law and have a multitude of cases where the bankrupt lost their homes to the mortgage company as a secured creditor. If the bankruptcy trustees or bankruptcy court judges believed there was good law to claim that these properties were unsecured, they would go after the property in a New York minute. However, no bankruptcy trustee or court in the entire country has tried to claim that these mortgages are void or even voidable.