If the gun was found 15 inches from his body and it was not residue on his hand, could the possibility be that he indeed was shot and his body and gun was staged to look like he was killed in the location where he was found? Now were there any fingerprints in the gun found near the body?
As someone who had major asthma in school I never went anywhere without my inhaler. Do we know if there is any recent contact with someone who he might have been meeting up with? Do we know if he planned to go back to school for his stuff? What belongings did he have with him?
There a lot inconsistency in the case. The gun should off have fingerprints, was there any trace on the gun ownership?