You need to read the whole entire act. Section 2 of the same act reads:
the District Court shall determine de novo any claim of a violation of any right of Theresa Marie Schiavo within the scope of this Act, notwithstanding any prior State court determination and regardless of whether such a claim has previously been raised, considered, or decided in State court proceedings. The District Court shall entertain and determine the suit without any delay or abstention in favor of State court proceedings, and regardless of whether remedies available in the State courts have been exhausted.
The direction of the Congress to the court to try the case all over again - which was not done - is pretty clear.
The de novo trial comes later. It appears that what Congress was expecting was that the Court would grant relief and then later -- probably after months of preparation -- there would be a lengthy trial. Congress did not anticipate that the judge would not grant relief based on the premise that the Schindlers would likely not prevail during the trial. I think Congress blew it.