I agree, it will depend on the forensic evidence. If there is clear DNA evidence linking CR to the crime, the defense does not have much leverage except letting Mollie's family be spared of a trial. The state does have a few options even if they insist on 1st degree murder: they can recommend he be housed in a prison close to his family so he will have visitors, they can not include a SA charge (if appropriate) so he can see his daughter in prison, they can allow for the possibility of parole after XYZ years. If the evidence is strongly against your client, as a defense attorney you'll be advising your client of these types of options to try to get the "best" outcome. A plea would also spare CR's family from a trial, so selfishly he has motivation to plea there even if he's not remorseful about the crime.