Been lurking here from the beginning. Excellent reasoning and sleuthing going on. Wanted to return to HG's intent for a moment. To do that I'm using the McGrady's video from the Cavalier Daily. It is zoomed out to the original frame size and gives a more overall view of what's happening.
https://www.youtube.com/watch?v=Dy43pVr2Ixw
My belief is HG wasn't lost at all. Drunk yes, but not lost.
McGrady's is located on the front of a two block square and Grady's Ave. (which is right next to McGrady's Irish Pub) and is a dead end street. HG only showed up on the Shell video once going toward the downtown mall. Therefore she likely emerged onto Preston from either 8th, 7th or Albemarle St. and then turned to go toward McGrady's.
McGrady's Pub has no adjoined parking lot therefore patrons park in the neighborhood surrounding it. If HG came down 8th St. she would have already scanned the cars parked down that street.
HG comes into view on the McGrady's CCTV video and walks to the front corner of the outside patio at :56 in the video. She stops and scans the area around her. She then walks to the other corner at 1:10 of the video and pauses again. She then exits the video and is gone until 2:56 in the video.
My belief is she has continued walking up to 10th St. and around the corner to further scan for cars parked nearby. At 1:35 in the video we see I male standing just outside the outdoor patio seating area. He appears to be a bouncer to me. At 2:56 when HG rounds the corner back at McGrady's the male immediately strolls to the meet her at the top of the ramp HG is walking up. They meet at 3:08 in the video and she passing him very quickly and he returns to the place where he was standing.
HG, in my mind, has cased McGrady's for a car she is familiar with. Why go up the ramp? She can get a better view if someone she is looking for is on the outdoor patio and also ask the bouncer "Hey have you seen ____?"
At 3:36 in the video HG crosses Grady Ave. and pauses one last time to look up Grady Ave. at the parked cars. Not finding what she's looking for she continues on.
Her next destination is the downtown mall. Think of that feeling you've had sometime in your life that you're missing the party, the fun. Thus to close the distance she runs for a while and that's what's caught on the Shell video footage.
YES, except I think she was not very drunk or lost. There has been a lot of exaggeration about that but she is moving pretty well and purposefully, and we have a lot of video time of her not drinking.
On the other hand we know she is going to a party and is no stranger to drinking (and this is reasonable, she is European and has been living with and experiencing alcohol for several years. Yes she lives in VA, but is in Europe every summer.)
We also know she is extremely sharp, worldly, witty. This is a smart woman, studious. No evidence of any interest in drugs, but like most college students knows how to party.
Her room has 20 or 30 booze bottles on top of the cabinet. How did she accumulate those, being under age? Well, people OF age buy it for her, of course. (PD should ask her roomies about that, "Hey, where'd all those bottles come from...?)
There are no drug deals, ruffies/spiked drinks, sex slave rings!
So what is she doing?
She's going to a party, and she is not going empty handed. She is going to buy something to bring, which is not a big deal to her except the silly US drinking age.
She goes right to McGrady's, looks twice in the beer garden for someone she knows, doesn't find him. Looks for his car, then looks for a third time at the front door. She goes further to the mall, and then finds him. First, they pass by each other going opposite directions and she doesn't see him. Then LJ wheels around to go the same direction, then off video passes the other group, calls out, "Hey, Hoo!" He doesn't know her by name, nor does she know him by name, only by sight. Hannah turns around and spots him, lets him catch up and discreetly tells him she needs some drinks for the party. (WG sees all this and bails.) LJ walks with her toward Tempo, now on the second video. He pops in, buys it, brings it out they part.
She heads back on Waters to try to find the party and gets to her neighborhood, but can't remember what apartment the party is in, texts she's coming but "lost". She is not LOST lost, she just can't find the party.
Then something bad happens.
LJ probably isn't involved beyond helping her out with the purchase but he isn't going to talk. He is black and she is white, young, connected. The police are not his friend. In his mind he might even get shot before this thing gets solved. Heck, they already took his car and ransacked his house! At the least the DA would need to give him immunity for buying for her (which he probably did in the past as well, for her and others.) But probably he still won't talk, and if you think about it from his perspective it makes sense.
I do hope they find her soon, sounds like a one-of-a-kind person. The world needs her.