i had the same happen today , so i helped it out because it had started shaking tuesday an a hole was in the side ,it would scream when i looked in incubater , so i was worried it was in to long , i dont know but it's doing great , it so cute
RUB VICKS ON YOUR HEN AN THEY WILL LEAVE HER ALONE , I KNOW SOUNDS WIERD BUT CHICKENS DONT LIKE THE TASTE OF VICKS , IT WORKS, RUB IT ALL OVER THE HEN, YES MESSY BUT WILL SAVE YOUR HEN FROM PAINFUL PECKING
find wood pallets usually u can find them free for the hauling an build a coop ,that what i did way cheaper , an u don't need anything fancy chickens need a roof over head, food ,water ,make sure they have room to stretch wings . an they be alright , in colder states makes sense to make smaller...
looked at your pics ,i more than sure it hen pecking ,ISOLATE her or they will peck her until she dies , they peck huge holes ,i had one that you could see her insides ,took over a month isolated before it healed , an it will heal ,i know hole looks bad but she will make it if you ISOLATE HER...
are you sure the other chickens didn't peck her or a rooster ? i have had roosters an hens do this to each other . i would cage her up an make sure it clean (wound) atleast a couple days so it can rest an heal .