For hatchling rhacs I place a tiny of CGD in the bottom of a 1 oz deli cup, then turn the cup on it's side and tap it gently on something to thin out the CGD drastically. I'm trying to make it paper thin so I can see even one lick and know they're eating and I place the cup in the enclosure on it's side so they can slide right in and eat. Place it close to where they hide facing them. I normally try to feed them 4-5 days after hatching and don't worry about it too much if I don't see anything. I agree with Haden, leave them alone and don't hand feed. There's just no reason to and you could stress out a young animal and fulfill your own prophecy of going off feed.
Try the feeding method I described and you should be able to see them eat. Also look for poop, the end result of said feeding.
And don't worry too much, they'll eat. Just concentrate on your husbandry being correct and the rest will fall into place.
No UVB necessary though. Crickets maybe once a week or so.