While the retired FBI profiler that BE interviewed in the below video had many interesting points, I especially noted 3 comments.
1. He thought that the video of the perpetrator makes it clear that he's an amateur.
2. He also thought that this perpetrator's DNA should be all over NG's house.
3. He noted that the perp had a small tattoo on the back of his wrist that can be seen in the video.
He details all of these thoughts, as well as many other insights, in his interview. Helpful observations, I thought.
JMO