Nah. He's a card-carrying azzhole. Always was, always will be.
If it’s shown that by reason if mechanical defect and the happenstance of a live round being in place to discharge when it did, whether the trigger was pulled or the hammer slipped, it’s going to really impress me with the possibilities of karma working in the world. It also opens up questions about the karmic impact on the deceased woman and her family.
“maybe he’ll learn a little humility and contrition”
That usually doesn’t happen with malignant narcissists. In his mind, it’ll always be someone else’s fault.