When the judge dropped the charges, it had to be done "without prejudice," which allowed them to re-file any charges. If the DA honestly thought he was innocent, he would have done so, but there was also societal/office pressure and the victim's family to deal with. If the judge dropped the charges "with prejudice," double jeopardy would attach.

Anyone seeking a clear and unbiased breakdown of this case should listen to Crime Weekly. It's a LONG one but worth the listen - as all of their stuff is! My opinion: he physically is the one who did it or had knowledge of the murder.