Devils advocate...
Do you think a go-around has more potential or likelihood to cause harm to the unsecured passenger than a landing?
I would assume with your "needs of the many" you are more worried about overall aircraft safety?
I think it's safer to land.
If you're landing, a single person self-selected.
If you go around and botch it, now you've got to worry about the procedure, fuel consumption, and all those other things you're volunteering yourself for.
I'd be very confident going to the office to explain my decision.