I've spent some time looking at a map, because obviously the information we know about her potential destinations (home/shady lady) don't seem to match up with where she was pulled over and last seen by a police officer.
I notice the charles b wheeler airport (MKC) is right nearby, however she'd have to pass the exit to the airport in order to get to the quickstop. However according to google maps, you can enter the airport from the north side as well. So if someone was looking to make one last stop before a flight, that might not be a bad location for such a stop.
The larger airport Kansas City International Airport (MCI) is further to the northwest. But, if you are leaving town and you want to reduce the odds of being seen or your vehicle being found quickly, that'd be a good choice and about just 15 minutes further.
Another thought, that others have mentioned as well, is that at 4:30 am there's not a whole lot of places one might go. Even Shady Lady closes at 3am according to google, so I'm confused by why she'd be heading there to meet someone at 4:30am.
If you look right to the west a little bit along the river, you'll see the Argosy Casino Hotel and Spa. A 24 hour establishment. Would be interesting to know if she ever went there for any reason or if that might be a potential destination.
I'd have to believe that they checked the airport already, but I think it'd be worthwhile to show her picture at the hotel to some of the patrons that would have been there that night in the hotel, casino, bars... etc.
In regards to the airports, she's be catching an early flight and I guess that's where her phone call/text data might come in handy. Who has she been communicating with recently that is out of state?
Unless there is a explanation for why she'd be heading to shady lady almost 2 hours after they closed, I'm going to say that she obviously wasn't heading there. She wasn't heading home.
So, some have floated the idea of a drug transaction. Is that area reasonable for such things?
Lastly, there are a bunch of hotels near the airport and I do think it'd be worthwhile to at least investigate if she was involved with any escort services. Her phone records might reveal such a thing. Airports hotels, casino hotels, are common places where an escort might end up at that hour. I'm sorry to bring up this topic, but I think we have to be realistic about what people do at this hour and in that area. Even the boyfriend saying it's common for her to not come home at all and maybe sleep over at a friend's house, is consistent with this topic. If finding her is the #1 priority, then being realistic should be a top priority over any stigmas regarding that possibility.