It makes sense because they know her, know what she's doing and how she's doing it (or at least they think they do), and they have already infiltrated her operation. If she leaves the scene, someone else who's possibly harder to deal with would fill the void. That's why the CIA would prefer to keep her around.The CIA want to watch her because she's dangerous. Or something. lol
I mean, she's Koko and she's loco, so it makes perfect sense!