The kid is lucky it wasn't me. I would have probably screamed it him.
I think you are doing all that you can, and I think the fact that it's eating and drinking is a good sign. The poofy fuzz and light weight probably slowed the decent and softened the landing. Keeping in mind that it is a chick and not a duckling, I will still mention that wood ducks and mandarin ducks often nest high in the trees - sometimes more than 200 feet up - and after hatching the mother flies to the ground and calls the babies. They jump down to her on their own. Chicks can be surprisingly tough sometimes...
I think you are doing all that you can, and I think the fact that it's eating and drinking is a good sign. The poofy fuzz and light weight probably slowed the decent and softened the landing. Keeping in mind that it is a chick and not a duckling, I will still mention that wood ducks and mandarin ducks often nest high in the trees - sometimes more than 200 feet up - and after hatching the mother flies to the ground and calls the babies. They jump down to her on their own. Chicks can be surprisingly tough sometimes...