Legal Question in Real Estate Law in Florida

You can call your broker and give him an ultimatum, but you are trying to push a rope up the hill. A closing date on a purchase agreement is only a "target" date, and reasonble extentions should be granted, to permit your lender to get docs submitted. If the short sale lender starts threatening to "put the home back on the market" etc, see an attorney about filing a lis pendens. If the deal falls through, then find a different lender, get a full pre-approval without conditions other than appraisal and titlework.