if he's still around, just hiding, or laying low, and we all know some hatchlings are quite skittish when it comes to people, he might be coming out of hiding and roaming about (looking for scraps of food and bugs) when no one is looking.
You can test for this by laying down some butchers paper or news print near where you think likely hiding spots are and sprinkling some flower or talc powder on the paper. Put a basking lamp on a stand over the spot . IF he crawls across the dusted paper you'll see tell tail tracks and you'll know he's still alive.
I know people who have done this when their small lizard has gone missing, and sometimes the tracks have given strong hints were it's hiding and they've recovered lost lizard.
Also, hatchings are great climbers, have you checked the top of the curtains and up high on climbable furnature.