There's something a little weird about all this. The original press conference said no indication of drugs or alcohol. People died. The boat was towed. I'm not sure what the police need a warrant for, since they can search with consent, and I can't imagine why the current legal owner would refuse to allow a search. Perhaps there's an insurance issue? Might the families of the friends be threatening to sue the Fernandez estate if Fernandez was boating while intoxicated?
The "odor of alcohol" sounds a bit fishy to me. This was a violent crash - a bottle could break and spill on anyone's clothing. But then again, the original report was no indication of drugs or alcohol.
The timing of post mortem test results depend mostly on the backup at the crime labs at any given time.
Lastly, it seems to be going on a bit long for a criminal investigation. The police should have been able to pull data from any ocean-facing cameras, GPS, examine the boat, interview friends, look at social media/electronic records, etc. by now. Perhaps much has already been done and the article just isn't very precisely worded.