I got interested in this thread not because I thought the abduction of Jacob would actually be solved ( I am amazed at how it played out) but rather, that I was concerned that an innocent man was going to be railroaded.
We now have a suspect who has a long history of sexual attraction to young boys, there is forensic evidence that he sexually assaulted a boy under very similar circumstances in a neighboring town months earlier and vehicle tracks, indistinguishable from his, found at the crime scene. He is the obvious #1 prime suspect. There may be others, including DR who have found themselves, under some quantified ranking system, as a POI with a number attached but those were based on what would seem the flimsiest of circumstantial evidence.
Certainly Sheriff Sanner was aware of Heinrich and the evidence against him before the DNA link to Jared was made. My guess is that he realized that if Heinrich did it, the FBI was going to get the credit. His only chance to solve the crime and gain the glory was in the unlikely event that someone other than Heinrich was guilty.
After Kevin came forward and he had a chance look over the case file, he found his "prime suspect". I am pretty sure the smoking gun; damning "evidence" was the fact that DR was middle aged and still lived with his parents. To this day, all the suspicion directed at him flows from that one salient fact.
It is time that Law Enforcement and us lookylous out in cyber land quit dwelling on missteps that have been made and start focusing on the real matter at hand: how to bring the predator who killed Jacob to justice.