Daytime is good, but nighttime I feel it would be a bit too cold I think.
Maybe wait another couple weeks till you put them out for the night.
Sounds like it’s going ok!
I agree with @rosemarythyme about the holes and covering them.
What are your temperatures at night? How's your weather been?
So you are able to keep them separated from the older girls in the same coop using the see no touch method?
By the way your chicks are so stinking adorable! 😍