A very odd flip-flop in the story
The premise of the entire show is her trying to figure out a way to break her brother out of prison. For about 7 episodes she was relentless in her tenacity in achieving that goal. And in the last episode, it flips to her thinking he humanely needs to be put down.
I thought this rather odd writing when you consider how much work she put into manipulating and scheming just about every character in the show to save her brother. It didn't make sense to end the show this way after watching her work the other episodes.