I get the feeling the frenemies all sensed this. As soon as the law showed up at Tony's apt early on the 16th, he called Amy and told her to call the police. Jesse also took it upon himself to call the police before they had a chance to contact him. On Day One, they all took pains to reach out to LE and drop a dime on Miss Casey, and have probably been fully vetted by LE by now. I think trying to pin it on one of her closer associates would be very difficult. Pointing the finger at someone outside the circle would be easier for Casey to do, but the complete lack of motive (and possible airtight alibis she would be unaware of) would make it a risky strategy.
After all, Baez has absolutely no way of knowing just who has been contacted by the sheriff, the FDLE and the FBI. I doubt any of them would lift a finger to clue in the defendant.