Thanks for that!
1 As I start to peruse the timeline, in light of my knowledge of that geography and the conditions that time of day, I think very strongly that the answer to "where was Prisma from 5:15 to 5:45" is fairly easy:
She was driving drunk, and angry (frustrated), and incredibly confused by the streets and hassled by the heavy traffic everywhere (even on side streets, at that hour). Some are one way, they run at odd angles, and it's a sketch part of the city. She MAY have been using a driving GPS (like Google Maps or Waze) or may not to get her home. But her path looks like she started on the way home but before she even got on I-30, she bailed on that idea and couldn't figure out where to go and how to get there. Maybe she was aware she was too impaired to survive the rush hour traffic -- the highway was almost certainly very clogged already, and it would NOT have been route/time of day she was familiar with. Much less drunk.
* Do we know the content of the call to Juan at 5:25 pm? Do we know where he lived (or where she would have reasonably thought he would be when she called)? Did she even talk to him?
* I would guess that she was trying to figure out where to go, or how to get somewhere safe, to get over her drunkness. It's interesting that she called him first.
* Do we know the content of the call to Ryan at 5:27 pm? Did she even talk to him?
It would have taken her ALL of that 30 minutes to drive drunk, confused, and lost to get to a place she knew (Ryan's apartment building).
2 I also am all-but-certain that she never was trying to get to White Rock Lake, or to her job, or was taking Hwy 78 (intentionally). Instead, she was lost-ish, and took East Grand (78) because it would allow her to go under I-30 and then head back the other way to the apartment building that she sorta knew. There were probably signs that guided some of her turns that took her to I-30 and then past it. She was dealing with one way streets, and the highway in the way, and all the streets at odd angles to the highway, and limited access ramps. And heavy traffic everywhere.
Her path was very circuitous, from all the reports called in. It's possible she was very aware of being drunk and was also trying to get somewhere to stop, out of sight of people who might report her, before she was noticed by LE and popped for a DUI.