I think the cell issue is key. I've always believed that the perp(s) used HE's phone to set up their alibi.
TedMac, I agree.. Imo, it would be logical to conclude this from known info. If true, it would also be logical to conclude that this was not an impulsive act/crime, but one that was planned out very well. This would indicate an organized offender, imo.
Although a serial offender has been ruled out by investigators in HE's disappearance. Serial offenders have to begin somewhere. Most are identified and apprehended early in their dark journeys due to the lack of experience, etc.
Imo, the following info on organized serial killers is pertinent and may shed some light on the person/s responsible for HE's disappearance;
http://www.sciences360.com/index.php/organized-versus-disorganized-serial-killers-2-22795/ - Organized Versus Disorganized Serial Killers
<sniped & BBM>
The organized offender leads an orderly life that is reflected in the way he commits his crimes. He is said to be of average to high intelligence, socially competent, and more likely than the disorganized offender to have skilled employment. In many instances, he lives with a girlfriend or is married. He may even be a father.
He will plan his offense before the opportunity arises often for weeks, months, and even years before acting. He is aware of his growing compulsion to act out his murderous desire. He will typically use restraints on the victim, and bring a weapon with him, which he will then take with him when he leaves.
Typically, the organized offender leaves three crime scenes: Where the victim is confronted, where the victim is killed, and where the victim’s body is disposed of (Vronsky, 2004).
The organized killer approaches his victims by socializing with them, charming them, or tricking them into a situation where he can overpower them. He typically owns a car, which he then uses in his crimes. He follows the reports of his crimes in the media and changes jobs or moves to a different city when he believes he may be detected. He is sometimes schooled in police investigative methods and he is constantly improving his technique with each additional murder.
The longer he kills, the more difficult it becomes for police to catch him (Vronsky 2004).