If you watch the video, you'll realize that the officer is on the phone with a peer. He is having a private conversation that was unfortunately and unintentionally recorded by his body camera.

I believe the officer is trying to use dark humor to develop a sense of detachment from a horrific event. His statements are clearly delivered as sarcasm, not sincerity. He is saying outlandish things in an attempt to avoid becoming emotionally overwhelmed.

He is coping, not denigrating.