His toes didn't look curled to me, it looked to be just the way he was setting. If you ever deal with curled toes, I'd recommend cutting out a small piece of cardboard, just big enough to cover the foot with the toes spread out, place the foot on the cardboard, spread the toes and put a band-aid over it to hold it in place. This is my little guy from earlier this year, before and after pictures.
Before

After putting the boot on


Two days of having the boot on, toes are fixed.

Wishing you luck with your chick, and glad to hear he is better!
Before
After putting the boot on
Two days of having the boot on, toes are fixed.
Wishing you luck with your chick, and glad to hear he is better!