I am surprised that I haven't heard/read from too many people how insignificant they feel the tone of "guys" is within the audio clip.
In my opinion, he sounds like he's trying to come off non-offensive and approachable. It doesn't indicate, IMO, any type of authority or familiarity or distance or anything, really.
It's the same way I'd approach a group of kids I knew or construction workers that were making too much noise or a barista at a coffee shop or a clerk at a store or my own children or a class I substitute taught in or anyone, anywhere really.
I guess my point is that I don't feel the tone or the word, "guys," itself is indicative of who this clown is or what he does or where he's from. I'm in a cranky mood from the lack of progress in this investigation; sorry.
I also recently finished The Killing Season docuseries and am so disheartened to know how many murderers lurk among us and how many people - women especially - are being murdered without justice. I'm mad in that this guy could be anywhere by now, killing who-knows-how-many more people. In this day and age, with a frickin video of the perp, how can it be this easy to get away with murdering two young girls in the middle of the frickin day?!