Also, might all this traffic indicate the possiblity of peekers, snoopers, curiosity seekers as well? Looking at DW's original statement to police the Monday he came back from his desert trip, he indicated a little girl who may have been Danielle (said he didn't know--he wouldn't have been able to pick her out of a crowd of ten, or even five, kids), was peeking in his motorhome as he loaded it. He came out of his house, he said, saw a little girl looking in his MH, said "Oh, hello there!" and she ran off.
Speculation: If there were little kids who entered the MH, perhaps when Danielle L. and her mother were living in it, or while it was left open and unattended while he loaded/unloaded on various occasions, who knows if Danielle VD may have been among them? The point is, there are a whole bunch of very different hairs in there, and "there is no way of knowing how long they have been there."