I've thought about this too.....what if JR or CR or one of the others did something else to P*ss off their dealers? The "big guys" could have showed up and taken LS, killed her - whatever. This could be a VERY big reason why the kids won't talk - they're scared to death! IMO this would make me think a bit differently of them.....they would go from maybe kids who are scared of getting in trouble, to kids who are scared for their lives or those of their families. Yes, I know this is really grasping, but stranger things have happened.
Also, someone a few posts back mentioned heroin. I highly doubt that's what they were using. Heroin is HIGHLY addictive and you can usually tell a Heron Junkie from a distance.....this drug completely alters one's appearance in a very short amount of time b/c the person becomes addicted very very quickly. They will do almost anything to get their "fix". Their faces might be broken out, very skinny (almost emaciated). Unless this was their (all of them) first or second time to ever use it, it's just nearly impossible to be caught up in heroin and making 92's on papers!
I understand that LSD is REALLY big on campuses now, as are mushrooms and other psychedelic mind-altering drugs. Bath salts and herbs (such as Salvia) are also quite common. Youtube Salvia and watch how kids react on that - scary.