As difficult as it might be, best to move onto a better opportunity, as there are plenty of them out there. The lenders have no liability and to be honest you would just be wasting your time and money to pursue them further. Perhaps an REO property or property needing work. Many times great opportunities are to be gained in these types of properties. I really hate these kinds of stories, but unfortunately short-sales are a gamble at best for everyone except the lender.
I hope it all works out for you Sam,
The buyer can go after the seller for damages. The RealtorsÂ® can go after the seller for commissions. By the way the next door neighbor can go after the seller just becasuse. You can sue some for just about anything but getting the money is the hard part.
If you do it soon enough you could lein the property with the judgement from your court case and watch the lein be set aside in forclosure.