I might can offer a little insight or info -- I am a recent alum of Longwood U, and have lived in central VA most of my life. The Pastor served my grandmother's church, as well as a large portion of my large, extensive family.
From what we've heard, it was Emma's father who took the kids (yes, I will call all of them kids) to the MI music event. Have also heard that Emma's mother was out of town, perhaps at a conference, and once she knew they were home she called but with no answer, and decided to return home.
The father/pastor was at church on wednesday night, and made phone calls on thursday. Apparently the last person to speak with him was a family member of mine, who is suffering a life-threatening illness. I don't know a lot about Mark, but everyone I know who did is adamant that he was very attentive to his church flock, and there for them in all their cares and woes.
The statements about Farmville are all true -- it is a beautiful little town where nothing like this has ever happened. Longwood's campus is practically pastoral, a mix of lush green and neo-classical style buildings.
Regarding those who marvel at the daughter of a prof and a pastor would wind up like this, and that they would allow a stranger into their home, OR that they would accompany their daughter to the concert/festival -- I can only offer the following: Until you are the parent of a child who changes overnight and scares you to death with their disappearing acts, strange behavior and attire -- your opinion is WORTHLESS. My son went through a phase where he wore black, had piercings, the whole bit, spoke of satan, etc...ran away from home. We lived in fear for his life, and had only ever been loving and devoted towards him. There was nothing we could do. I even took someone to court, someone who was harboring him and allowing him to pursue his "chosen" lifestyle -- but guess what? He was 17 and the courts refused to intervene, even though he clearly was a minor. Perhaps Emma's parents had already consulted their lawyer and realized they were on their own. Thank goodness my son survived and is now a successful young man with a beautiful family. I was lucky. Emma and her parents were not.
So, I completely understand why Emma's parents felt that if they could keep the situation contained, have some sort of control, by accompanying her to the concert, by letting Sam stay at the house (tell me, what do you think would have been the alternative?? She would have left with him!) I totally get what the parents were trying to do. And they gave up their lives in an effort to try and save their child. then again, maybe if she had run away she would still be alive. If parents are regarded as the enemy and you're staying in the enemy's house, who knows what might happen.
As an aside, the whole satanist thing is laughable, since there is no proof of the existence of such a creature, and even if there was, he is still part of the Christian canon, therefore, when a Satanist mocks Christians/Jews/Muslims, he is really mocking himself, too! The whole goth movement is laughable and seriously followed only by the weak-minded/uneducated.