In the alley video, she has on the same clothes she left the house in so she didn't take time to go home and change.
She left the football game, made her way to H+F, walked the dog in the alley a bit, then was separated from the dog somehow, and the dog was found by residents - all within a three-hour period. That's a tight window.
What happened causing her to be separated from the dog, happened very quickly.
Suppose she went there to meet someone, but they were not there,,,so she walked the dog while waiting. That someone never shows - someone ELSE does and she goes with them (voluntarily or not). Another party 'cleans up' the RR and dog.