Also, while I'm here, I might as well throw my theory out there:
It seems that Colt and Molly may have been getting drugs from Conn, whether just some pot or the meth his family (father!) is known for. It has been said that the two did not have a good relationship with Conn, so I don’t see any other reason for them to have connected that night.
Molly and Colt probably didn't expect to spend more than a little time with him. Possibly he picked them up for the exchange and drove around a bit to avoid the suspicious swap between two cars in a small town parking lot. Somewhere on the way, Conn is speeding and comes upon the two police officers. Rather than get pulled over with drugs in the car, he does what is familiar to him and runs. I'm sure that whipping around and going 120 MPH was normal for him, as he is known to drive dangerously and knows the area well. Colt (who may have just purchased drugs) doesn't fight it because he is on probation and doesn't want to get in any more trouble either. I can see Molly being fearful during the chase, and Colt trying to rationalize it as it being in all of their best interests.
But then, they crash. Conn obviously knows where he’s at, and decides to flee on his own to his grandparents’ house. Molly and Colt flee into the woods, where after some time Colt breaks his ankle. I think this is when Molly called 911, but Colt stopped her because of the larger implications for him. I initially assumed Molly called immediately after the crash, but PMF (family member) left a comment on the OFMM Facebook page that said the 911 call came two hours after the crash is assumed to have happened.
Colt and Molly wander/hide, and start calling friends for a way out of where they are. Hours and hours have passed and a new day has dawned. Molly was calm at 6:00 AM on the phone, but by 9:30 she is a wreck.
At some point, possibly after Conn returns to the vehicle with family/friends to “clean up,” they set out and find Molly and Colt. By this time, both are exhausted, frightened, and ready to give up to authorities. It could be that they said this outright, or it was assumed so by Conn’s posse because of the appearances/attitudes of Molly and Colt.
Conn’s own father can be assumed to be making/distributing meth in the immediate area, and there are the seven other stolen/wrecked cars on the property that were discovered later. It seems Conn’s whole crew had many reasons to want to keep law enforcement away from there.
Colt and Molly realize that they are essentially trapped, and that someone there has a gun. Both attempt to take off running, but obviously Colt doesn’t get very far. I also read that LE said these were, in essence, split second decisions to kill, and that the incidences probably occurred between 10:23 and 11:15 AM. I’m struggling to re-find the references to these right now, but will post once I do.
Perhaps a neighbor heard shots go off at those times, or that is when Conn’s ‘crew’ (whoever they may be) can be shown by cell phone records to be together on that property, and then back at the house. I’m thinking if it is that shots were heard, it’s possibly because Molly was able to evade them for a bit before being found and killed.
In any case, I believe Conn is absolutely responsible for a horrific crime involving these two young people. I’m sickened by the way his family ties were able to hold this case at bay for a full year, allowing them all ample time to search for and destroy evidence.
ETA: The calls between Conn's mother, aunt, and girlfriend in the early morning hours are very concerning. I believe they were all conferred to figure out what to do, and get their stories straight.