Just to play Devils advocate here... Is there a chance someone else could have passed by your truck when you couldn't see it and stole your phone? You just said yourself there was a point in time when you couldn't see your truck. If it was parked far back in a driveway somewhere where people wouldn't walk by it then it's understandable that he is the main suspect, but if the truck was close to where there are passerby's then the possibilities open up in a big way.