Does your coop look like the OP's? They have 7 chickens in it now.
That coop looks like it should have 3-4 birds max. That is why they are getting a bigger coop soon.
The new coop will not arrive in time. I dont hold much hope for the chicks.
Maybe i am over cautious with my broodies and chicks, but it works for me.
I allow the hen to be alone with her chicks for about 2 or 3 weeks max. Then at night i put her & chicks back in the coop (apple crate on its side with straw bedding). The next day they are out foraging.
Stacylinlac, Please let us know the outcome of this.
I wish you all the good luck i can.