There was not one shred of evidence to link this crime to Casey nor anyone else. No fingerprints, no DNA. How this was accomplished beats me. There was no slipups to find and connect.
Now, Casey may be relieved for the moment. But she will forever be in her own prison. Not a prison of remorse over Cayley, but she'll never see life again as she hopes. She can't go out and be seen anywhere again, will she be able to trust anyone again? People are already lined up for lawsuits. Any royalties she gets are taxed, not free and clear. For the next few years she'll be paying out a huge amount of her new found free money to others as cases settle. All this is going to upset her greatly. She'll lead a very lonely life, coming in contact with new friends who see her as a free ride to private parties etc.