You’re right and I don’t think the WM had a traceable electronic device on him, as far as we know. I was more surprised he possibly went close to Bayview (if I’m correct about the address.) Why the circuitous route? And why didn’t Detective Yim do a test call there?
Detective Yim chose a few specific dates looking at cell tracking and data. I’m wondering if people involved in the murders were in the area at those times previous to December 13th. Kind of similar to Kohberger in the Idaho murders.
In the Long Island murders, the alleged killer used a burner phone, but made the error of sometimes having his own traceable phone near it, and near his work and home, iirc.