I guess the thing that bothers me is that AD said that they'd never see Shaniya again. I know everyone's different, but I'd be all "hells to the no!" and drive the relatively short distance. I used to live in that area; it's really not that far. Just on the pretense of delivering more clothes, some favorite toys, etc. This child, for all intents and purposes, was undergoing a change of custody, per her father. Surely she'd need things or ask for things. Surely they'd insist on bringing more stuff down, even if they had to make excuses. "I just wanted to help you out by bringing more clothes, toys, her favorite book..."
I'm so sorry if this sounds classist or elitist, but if I had a child that had been living in comfort and in this case relative luxury, I'd have a hard time leaving her there without more oversight. It's not the trailer thing. Lots of fine people live in trailers. But it was rundown and since it was a one-night stand, they couldn't have known what the people were like around there.
I'm not blaming the dad and aunt. Goodness knows they must be absolutely distraught and miserable. I just think we're missing something. Maybe AD had something to hold over his head. Maybe she made some scary threats that he didn't take seriously and now he can't bring himself to revisit it. I don't doubt his grief and his innocence, but there are two sides not meeting up here. The image of the doting father and aunt who lavished so much love on Shaniya, and the fact that she was left at a ramshackle, dirty trailer with only a couple days' of clothes and no one drove down there. Did AD request some space to make it worse? For you parents out there, would you be able to grant that space?