Missing Chicago Postal Worker Kierra Coles Believed Murdered -- Could Cell Phone Tracking Break the Case?

Here's a case out of my home town that seems like it should be very solvable, for multiple reasons.

NBC Chicago
“She didn’t disappear on her own accord," says a Chicago homicide detective"

Although she wasn't on duty because she had called out sick for the day, pregnant Kierra Coles was last seen on CCTV footage in her USPS uniform.  Her family is contending that it's someone else wearing her clothing. 

Either way, whether it's her or someone stole her uniform, that should involve the federal Postal Police, and bring all sorts of additional resources into play.  It shouldn't be Chicago homicide detectives getting around to it years later.

Also this is most likely not a whodunit.  The man in her life, Josh Simmons, behaved extremely suspiciously, seen accompanying Kierra to an ATM where she made an abnormally large withdrawal of $400 despite normally being very cautious with her spending.

An unidentified man was seen driving back to Kierra's apartment alone, parking and exiting her vehicle through the passenger door for no apparent reason.  Kierra has not been seen since.  It's believed that whatever happened to Kierra happened within a one-hour window. 

Josh subsequently  moved out of the area with the mother of his other children.

So while there are no charges against Josh at this time, the Chicago detective is confident that Kierra didn't leave of her own accord, and that she's not alive.  My hope is that they can use the same sort of cell phone technology that was used to triangulate Rex Heuermann and his alleged victims to track the time and whereabouts of both Josh and KIerra beyond any doubt.