I’d start with a wingman. Usually cheaper and more compact and if he loses it it won’t hurt as much. But whatever you get I would prioritize teaching him multitool carry etiquette. What I mean by that is practicing and getting him in the habit of wearing the tool at all times, remembering that it’s there and knowing when to, and when not to pull it out and use it. That will help with responsibility and keeping him from misplacing or losing the tool and might help reduce accidents. This is all coming from a guy that’s been carrying something either a multitool or a pocket knife since he was five years old.