I had a pullet that nearly the same thing happened to. First of all, don't put gauze on it. That was the only mistake I made. I spent 3 days of 3 times a day picking threads of gauze out of the wound with tweezers. She was an incredible patient.
I didn't read this thread all the way thru but I thought I would at least tell you what I did.
I first cleaned out the bare flesh and I trimmed the feathers on both her neck and the piece of skin that was hanging. I smeared neosporin (without pain reliever) on the raw flesh with a q-tip. Then I placed the skin back over her neck and streached it the best I could and I wrapped her neck with gauze to hold it in place. I didn't have the stomach to sew it back. I have this thing about needles peircing skin. Anyway. I kept her in a 20 gallon aquarium in a quiet room with a screen over the top and a weight on the screen. I provided her with food and water. She had hardly any room to move around and that's how I wanted her to be. Confined. I didn't want her to move around and make the skin displace. Anyway, the next morning I went to take off the gauze and ended up having to slowly cut it off in patches. Thats what I worked so long picking out threads to avoid damaging the healing process. I kept neosporin on it for about 4 days. I also kept the aquarium clean. She'd poop and i'd clean it up. Her area was kept completely clean. I never gave her any antibiotics other than the neosporin. When she no longer had a scab she went back outside. I didn't put her with any other chickens till her feathers grew over the part that the skin didn't cover. She never grew feathers in that spot.
So if you've clipped that skin off, she will heal as long as she don't get an infection. I would think that other chickens will notice that area where there are no feathers and probably peck at it. If she gets bred the roo normally holds on to the feathers on the back of their heads. If she don't have any her skull will be getting damaged. Thats just what I figure what will happen. I can't say for sure.
It was a couple of months before I put mine with any chickens. By then she was so spoiled she dominated the hen house. She was the favorite of every roo I put in the coop. And she laid the biggest brown eggs everyday no matter if it was cold or hot. She ohly stopped once when she went in moult.
Please keep us posted how she's doing.