Continuity mistake: Before Hanna says goodbye to Ethan when they are old, she has a glass of lemonade but in the next shot the glass is gone.
A Dog's Journey (2019)
Ending / spoiler
Directed by: Gail Mancuso
Starring: Dennis Quaid, Josh Gad, Betty Gilpin, Jake Manley
* SPOILERS AHEAD* At the end of the movie, CJ, and Trent get married and have a baby, not long after Ethan dies from old age. And then Bailey (Boss Dog) dies too. The Ending is Bailey running through clouds, and it shows every type of dog he has been. Then Bailey reunites with Ethan, in a place that seems like heaven. They are running through a field, and the movie ends. It's a pretty happy ending.
Answer: Just because they only caught her doesn't mean that they didn't get anyone else. She was there at the party so she may have been able to tell the police who all was there that night or give descriptions of people.