I don't see this Perp as crazed, as see them as someone who likes to dress up and play cop. Has a strong desire to be in LE, but never will be. So not crazed, but perhaps of diminished capacity.
I know many of you think this was a well organized crime. I'm truly struggling to agree with that as I look at the video for the nth time. He is meandering around, dragging his hand on the wall, trying to open some doors half heartedly and failing, and was surprised when the Victim walked his way, and presumably upon him. Nothing about what I have seen on the video appears well organized. Rather, to me, this appears to be a two-bit vandal/thief who was startled and lashed out.
Again, all of you have had 43 threads to study and analyze this. I'm just offering up my honest reaction with fresh eyes. Looks like some nut job with a cop fantasy bumbling around looking for items he call sell quickly, and seemingly enjoying doing damage in the process.
Just one amateur's opinion.