DNA is not only in particles on the skin. Hair, saliva, sweat, semen, all contain DNA. In that LE felt it was important to obtain a DNA sample from Shawn Adkins I believe DNA may come into play here.
The sheet. Shawn Adkins would have no reason to have body hair on the sheets in Hailey's room. What if pubic hair was found on the sheets? What if there was a used condom or condoms misplaced during a struggle or carelessly discarded. (this actually happens quite often in crime scenes).
What if there were spots of blood from a struggle both from Hailey and Shawn. Semen- posters before me have addressed this issue quite well.
What about other forms of evidence besides DNA?
Hailey was in school, she was in church, she was in sports. She was very close to one teacher. Teachers, clergy, coaches, the school nurse all required to report anything they know about any possible child sexual abuse. Had they been communicating with child services before Hailey went missing? WE don't know but it is a possibility given the swift action of child services to remove DD from the home.
What about the locker search. What did they find in Hailey's locker. Books? A note or notes to and from friends, notebooks, certain musings perhaps? How about a diary? Hailey's own thoughts about what might have been going on in her life. What about possible pictures that Shawn might have given to her? Or personal notes? LE knows what was in that locker, we don't. But I have a feeling it may be important.
What about the tool shed. They took items from there. Did they find DNA from Hailey on any of those items?
The masks. While Billie said there was one in the house and Shawn only used them to trade. Shawn made a decided point to state that Hailey wore the masks while watching horror movies. Why might that be? Could it be because LE confiscated 3 and knew they would find evidence of Hailey's DNA inside? What about the xbox? What types of games or movies had Hailey been playing. What was on the CD they found in Hailey's room. What else did they find in Hailey's room? Did they find any evidence of drugs(since Shawn claimed she did drugs)?
The phone pings are another indicator of what went on.
What about the drugs that Billie admitted to buying on Monday night. What types of drugs were found in the home?
The landfill searches seemed to be very important to LE. What did they find? Because while NG producer said she was told they found evidence, LE wouldn't confirm it. Why? Maybe because they would not tell BD anything about what they found knowing she was a POI. Keeping any evidence very guarded knowing BD was still actively involved with the suspect.
I think the most important indicator that something is seriously pointing in the direction of Billie Dunn and Shawn Adkins is that the communication and updates from LE ended a long time ago.