I know you're done with this topic, but I just wanted to follow up on this.
The link you provide here is information about a specific piece of software - Kismet, which ironically I did come across in my mission of discovery.
Kismet is a system that must be installed by the end user and actively in use at the time these activities occurred in order to do these things. It is not a consumer device, it is not available to be installed on a consumer router, it must be installed on a linux/unix network server. There is a similar application that can be run on a windows network server.
And perhaps unsurprisingly, there are a fair number of people concerned with the privacy aspects of any commercial networks that might utilize it.
That leaves your second suggestion - BK's phone records. While all my research turned up zilch on routers logging this info, I didn't even try to see if cell phones record it. That was my logical conclusion - that either the "touching" was logged on BK's phone or by his provider (which I believe is in Pennsylvania).
The only other possibility is that SG was just confused as I have never heard a peep about it from anyone else. That seems like a viable proposition, but when I watched him saying it, several times, it just didn't seem like he was confused at all.
So I'm left just to scratch my head on the whole thing. Which is why I said I'm not convinced that it can be tracked.
But I'm open to being convinced!