I initially thought that the reason the case was dropped was because of Stingray, as you can read.
Turns out I was wrong, it was for a much more primitive reason. The remaining witnesses clammed up when his mama had two of the witnesses rubbed out.
MPC is mentioned here. Let’s see if she brings a death penalty case here. While the initial murder was the sort of TNB that doesn’t warrant the use of the death penalty in the modern paradigm, even if the suspect was at least 18 at the time of the murder, and in this case, he wasn’t, murdering potential prosecution witnesses is such a murder.