The theory of Chinwe being a prison guard or some kind of law enforcement has been knocking around in my head. She does know how to choke a dude out, *sorry Saul. Anyway if she had a hand in taking Bill Roberts down, putting him in jail for life or throwing him in solitary, then leaving her alone is revenge.

Bill "Pinstripe" Roberts must have recognized her voice or something and decided that since she put him in jail/solitary then he would put her there too. He killed or captured everyone around her and left her alone. She basically is in a jail of her own making and Pinstripe made it solitary.