The lighting has played fits with web detectives. I thought the same thing and why wouldn’t one draw such a similar conclusion when using this particular image?
My hunch was that it matched the looks of the recently married cop, that killed himself within a day or two of the shooting.
Someone is taking the liberty to change the exposure/lighting/shading of the images for reasons that remain to be seen.
Here's the original video, cued up at the relevant time. You can see it is a white middle aged man wearing glasses and has a receding hair line. He also appears to be wearing black gloves.
https://youtu.be/PfiS8MsfSF4?list=FLrPoNIjxkO_vKNOEz0cdTtg&t=2088