I just now saw this thread and due to time involved have only read every other page. This is my take.
LL is a transient.
The shirt most likely came to her used and the club printed on it means nothing.
I believe the items in her bag came from a) a truck stop B) a shelter or C) a convienence store.
IMO coming from one of these places would explain why they are of an unusal (smaller) size and name brand.
If she had been riding with a trucker, it's possible he stopped at one of the truck stops to shower, eat, and do laundry, or even to sleep in his truck and she might have been doing one or all of these things while he slept. When she never returned, he left w/o her never knowing her fate. OR, maybe he let her off there and went on his way.
I'm familiar with the big truck stops as I spent 2 weeks on the road with my son and his wife when they were team drivers . These truck stops have everything the drivers need on the road away from home. We'd stop, shower, do laundry etc.
So-
LL could have been showering and doing laundry and walked away from the truck stop. Her clothing could've been back at the truck stop being laundered but she took the items in the bag with her rather than leave them because she was afraid of them getting stolen.
If she were only showering, she would have still had the items with her for the same reason.
As for the dentures/toothpaste-
My husbands step mother wore dentures and only took them out to brush them with a reagular toothbrush and tothpaste and back in they went- she never soaked them.
Also, if LL were on the road and had no toothbrush only toothpaste, perhaps she held them under a faucet and rubbed them with her fingers with toothpaste.
And maybe her toothbrush was knocked away from her on impact of the accident.
Just throwing my thoughts out after skimming through the thread.