If he didn't make it home, then went voluntarily with someone else or kidnapped on the street. I would think there would be video. If left voluntarily after arriving home, is there a place where he might go? Friend, comfort place, etc. Which made me think of an addendum to leave voluntarily. Leave voluntarily , then get kidnapped. Its a little out there unless he went to meet someone, and that someone was not a nice person. If taken forcibly, then what direction? Out the back? He was so small and lightweight he would not be hard to wrap in something and carry out or even push or pull into a vehicle.
I am leaning towards met up with someone voluntarily and things went sideways. This is another of those cases where there is something just bothering me and I cannot quite place it.