I would try to spend some time with the chick hand feeding it. Soften chick starter with some hot water in tiny quantities so it's like cookie batter and hand feed. You might even use some cut up worms to tempt the chick. I've used either meal worms from the pet store or red worms from the bait shop. Rinse well, put in a baggie and freeze. Cut wormsicles into thin slices and hand feed when no longer icy. Nothing like a hand full of worms to make a best friend out of a chicken.
I'm a big advocate of talking to your birds too. They learn your language quickly if you continue to call them with the same words and vocal tones. When the chick learns your voice it will be calm when it hears you in the yard. When I call my girls with treats I imitate a mother who calls her chicks when she finds bugs... she uses a more urgent and repetitive short syllable buk buk buk buk buk.
Btw, when you walk up to a chick, you are a dark silhouette looming overhead, and their natural instinct is that this means danger, so it's no wonder your little one is in a panic. It saw what can happen with dark things overhead so perhaps now try to approach it in a way that isn't going to alarm the chick.
Years ago I had numerous peafowl flying free. When one would cruise over the chicken yard the rooster would make his long low alarm call of brrrraaaaaawwwwwwwwk and all the hens would immediately call their chicks to run for cover. They can't discriminate a predator from anything else; it's the dark silhouette overhead they fear.
In the meantime, hang 3' long red mylar bird repellent ribbons off of fence posts, branches etc. all over your yard. They will deter hawks, blue jays, and crows, which are all predators of chicks and eggs in nests. I've a pair of hawks nesting in a tall cedar a block over, but it's in full view of my yard and I watch the parents going back and forth to the nest. For good measure I've 3 large plastic owls on tall garden stakes stationed around the yard too. The wind catches the owls and they move in the wind and look life like. The owl is the natural enemy of the crow so I'm hoping the hawks won't want to land here either. So far they have both kept out of the yard.
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