Police said Claudia Cabrera was driving and her husband Jose Luna was in the passenger seat when they ran a red light near USC on March 29. Adriana Bachan, 19, was struck and killed while crossing Jefferson Boulevard.
Police said Luna even lifted Garfinkle's body off the windshield before fleeing the scene.
For days, Bachan's mother pleaded for the suspects to turn themselves in. Cabrera was eventually arrested in Mexico, and Luna turned himself in.
The family of Adriana Bachan was told to show up to a downtown L.A. courtroom Friday for a hearing because Luna and Cabrera were expected to accept a plea deal in the case.
"We wanted to take the plea today for the simple fact that Jose, and it seemed that Claudia, wanted to take responsibility for what happened. It appears that the lawyers have talked them out of it. We could have just put this all behind us," said the Bachan family spokesman John Welch.
The move would have meant that they could skip a trial and likely go straight to sentencing in this case.
But according to the family, the deal fell through last minute, and now they have to wait for a trial for justice to be served.
"We're so disappointed," Alexandra Bachan said.
"Six and four years is nothing compared to the life sentences that my parents are serving in their grief," she said.
The suspects are due back in court for a preliminary hearing on August 10.