I have no reason to believe that AJ used drugs, much less anything serious enough to kill her. However, even if that were true, WH and the posse would be guilty of something incredibly serious by treating her body, friends, and unknowing family with disrespect, wasting incredibly valuable resources in a search for someone they hid, and lying to the police and public the whole time. Then they publicly bash anyone who asks questions.
And what type of dirt would solicit funds for a social media missing persons alert system and offering spokesperson services to real grieving families when they knew the truth? All that is pretty bad as it is considering the timing, but if they knew it was a sham? Wow.
ETA: Killing AJ out of rage might be less reprehensible. Not much, but that alternative is pretty bad, IMO.