You could try some Poultry Nutri drench it can be given straight so you could try putting a drop right inside the bill , you don't ever want to try and squirt anything down there throat they can aspirate it into their lungs. start with a drop then increase to 2 drops 2x a day You can get this at TSC Hopefully a few of of vitamin therapy will get it up and walking. Please let us know how it's doing.
How old? you say hatchling but does that mean today or yesterday?