Thank you everyone for your replies! I think my post got lost in the masses and I had about given up. We're on week two and you guys were right; they're doing great! In case anyone else is in the same situation, or just curous, here's what's happened since:
Henrietta stayed in the box with the chicks for the first 2 full days but the morning of the third, she led the chicklets out like she was on a mission. It was a little chilly that morning (and I was being a helicopter grandma) and it looked like the chicks were wanting to huddle under her in the cold/damp grass, so I shoo'd them back in the coop and closed it for a few hours until it was warmer/drier. They spend the rest of that day, and every since, outside just doing their thing. I saw one of the chicklets slurp down a worm on their first day out!
Henrietta is a good and (I think) happy mama. She's has chased off curious cats, dogs, roosters, and turkeys. She makes the same "hey, get your food here!" clucks that the roosters do when she I give her "treats" (dandilion stems and chick starter feed). They're pretty skittish yet, but I can handle them and Henrietta doesn't mind. She's slowly taken them further from the coop and now they make round of the whole (roughly 1/3 acre) yard. I love watching them take dust baths. Most like it but one looks mildly disgusted the whole time
I had one scare this weekend when Henrietta took them out first and then the turkey's did their morning race across the yard and one full-on stepped on one of the chickets. I was sure that the poor little think was going to be totally splat, but it was fine! I've been watching closely and there no sign anything happened. So the good part of that is that one of my chicklets has a name now: Squish.
This afternoon it was drizzling and I saw Henrietta under a bush and asked where her chicklets were and suddenly little yellow faces popped out from under each of her wings and one from her butt-fluff. Cutest frelling thing I've ever seen! I don't have my phone on me at the moment, but I'll post a few update pics tonight or tomorrow morning.
Thank you everyone!