i just had kinda of the same thing happened to me just 4 hours ago. I left the egg in there and it hatched but we think it died shortly after. I heard that if you need to nurse a chick most likley it wouldn't survive for long hope this helps
I give my birds watermelon, corn,Cheerios, meal worms,and apples.
From what I know don't give your chickens anything in the onion family.
hoped this helps