There is no fallback if patient's wishes are not found. That is a necessary prerequisite, for now.
Florida Chapter 765 taken as a whole is, IMO, internally inconsistent; but by choosing through the clauses in a suitable path, the statutes will read as authorizing the outcome of the case.
Maybe I'm just burned out on the whole matter, especially the legal issues of this case, but if that's so, why was the issue of whether Terri was in a PVS even before the court?