That is great about the thermostat! Sounds like your husbandry is great. Should you get trouble with humidity you can change to a substrate that holds it better, like Repti Chip or something. Until then, mist as needed.
However, now it is really important that the little guy gets his "down" time. That means NO more handling and as little disruption as possible.
With the tub not being in a rack, I would wrap a towel around 3 sides. You want only one side open for viewing, the rest (top, bottom, sides) should be solid. Will make him feel more enclosed and secure.
Then wait a couple of days. If he cruises at night, he might be looking for food. Ideally one evening you should notice his little head poking out of a hide. You could then place the food in front of the hide. Hopefully he would strike, if not, leave it and leave them be. The food should still be small enough not to cause damage to the hatchling, if you give live food.
That hatchling is skinny. His backbone is quite prominent and his stomach is completely concave.
But I've seen them bounce back from this. Its good that your husbandry is already spot on, now you just need to keep the stress level down and try feeding.
Hopefully it will work.
Good luck, that sure is a pretty little thing