The pair were charged last week with carjacking and kidnapping Caballero from the parking garage of the Trump Taj Mahal Casino Resort on May 21.
Caballero was in town to celebrate his daughter's 22nd birthday.
His remains were found on a farm west of Atlantic City.
Kisby's lawyer, Steven Scheffler, said he expected the charges to be filed, adding that his client's side of the story has yet to be told. Arno's public defender could not be reached for comment.
