The killer is shown going to confession several times, but at no time is he specific about his sins. Absolution cannot be given within the constraints of what he shared with the priest because the confession was too vague. That's why what is said in confession cannot be revealed, as with a defense attorney, the confessor needs to be completely open and honest with the Priest.
After the reporter gets killed, Robert Carradine, who plays Everett/Gary/David, can be seen as Everett in the interrogation room with scratches on his right wrist. Everett didn't receive those scratches, the killer did. Everett was in jail the entire time.