Have you ever given up on a hatchling who won't eat?

[Gemini Pythons]

Thank you for all the helpful suggestions! A few more question were asked, so i'll answer those:

So, things I didn't see in your list that would be worth trying:
1. Live hopper mouse - We did try a live hopper as well (technically they were a fuzzy based on weight, but we picked them as they were really just a runty hopper- eyes open, more active). It didn't work and actually just stressed the baby out (trying to escape their tub)
2. Live hopper mouse or fuzzy rat scented with ASF - This is a great suggestion and we'll try it out!
3. Live ASF - We are unable to get live ASF in our area

Also might help someone with more experience to have more details of your rack and tubs.
- What size tubs? (Dimensions or common model i.e. V-18, 6qt, etc.) We have tried VE108-8 and Iris MCB-SS shoebox. Currently using a VE 108-8 as it is darker and more snug. No behaviour observed that would indicate tub size is a stress factor.
- Clear or opaque? Semi-opaque (we can see blurry movement or an outline in there if a snake at the front, but otherwise nothing)
- 1 hide or 2 hides? 2 hides
- Substrate? (Paper towels or something they can burrow into?) We have tried paper towels and coconut bedding

What else is in the room as far as smell goes? Any dogs/cats, any non-feeder rodents (like gerbils?) that this one may be waiting for, any larger lizards or other potentially intimidating smells, any odd chemicals used in the area like lysol wipes on non-reptile furniture or anything like that. None. We have a dog and cat, but they are not allowed in the room the baby is in. We disinfect with F10

I haven't worked with newborns as of yet, but I do have one finicky eater and when she does take f/t for me, I cannot be at all visible in the room (even 8 ft away not moving), it must be very dark, and if I move her tub closed or at all unless it is mid-strike she will drop her meal and refuse to eat that week. (She will take live and when it is struggling still, I can slide the tub closed and leave the room before she notices. If she sees me through the tub via heat she will also drop and refuse to feed) We have tried to minimize our presence as much as possible during feeding (whenever possible we close the tub and leave the room. The room is dark. Interestingly, the baby has never been fearful of us. It was a shock that they have been such a bad eater. They were very calm and not fearful from the get-go (no hiding if they saw us, in times we've had to handle them, they behave as i would hope a snake does- calm and curious, but not trying to get away or balled up)

On that thought, have you attempting being around a corner from the tub so as to be not visible? Or considered that the movement of the tub may be startling this one out of feeding mode? And what time of day/brightness in the room do you feed? Yes,we have. We have also tried feeding at basically every time of day. Morning, noon, afternoon, evening, night, middle of the night. We feed all of our snakes after 10pm regularly.