Ok I just watched the news conference, I have a theory.
What if the father hit nalani/ left her unattended, left drugs out etc.. and nalani was seriously injured and or unconscious..an argument breaks out between sharena and the friend, sharena wants to call an ambulance/ take nalani to the hospital, the friend is concerned about the police, sharena tells them to get out and takes off with nalani. The father and friend immediately decide to place blame onto sharena and call 911 to clear themselves. At this point, I don't know why sharena wouldn't have called the police and/ or an ambulance, maybe the father has some kind of dirt on her? Maybe if drugs were involved, sharena had something in her system? (Has she and the father and friend been drug tested?) I'm thinking nalani passed away in her vehicle, (sharenas husband did say her car was silent while on the phone with her, after the video call was cut off), and she panicked and got nalani out of her car, and then turned around and went the opposite direction not thinking rationally.