Hi, sorry your hen is having trouble.
Did you figure out if it was your own flock or a predator?
I would stop with all the eggs, yogurt, and meal worms... they may be higher in protein than layer feed... but they are extremely high in fat and may be missing other key nutrients... for example eggs are 34% protein and 64% fat by energy. Live meal worms are 48% protein and 40% fat. They are good source of nutrients as treat but NOT on a regular basis. There better choices that won't cause fatty liver syndrome... like a chicks starter feed, gamebird feed, turkey starter, flock raiser... you get the idea. Rinsed canned tuna, cooked ground beef or chicken. I personally NEVER use layer. But your gal... may need some oyster shell on the side or some grit if she has been in a kennel for long. While I know that protein promotes feather growth since they are made from 90% protein and it's amino acids... I'm not sure how important of role it plays in general healing of skin. I would think a vitamin and mineral supplement like rooster booster Poultry Cell... might be more helpful. But I like your thinking, good job!
Keeping her in view of her flock would be advised so that she will integrate back with them easier or she will be treated as a new comer and face some pecking order difficulty upon return.
Sounds like she isn't in shock... since she is eating and drinking, that great news! If that was done by a predator... my flock actually doesn't obsess and the birds stay together... attracted to red, is BS in my opinion as their combs and waddles are red but left alone EVERY day. Blood does attract them, especially if they taste it. You might try some supervised visits and see how it goes.
Leaving the wound alone so it can scab over might allow it to heal faster... not sure what your cleaning is... but we do produce our own antibodies to fight off infection, and to me part of that fight is the oozing that pushes debris out... I realize this isn't the correct answer for everyone.
I did have 2 birds scalped much worse than that, one a chick the other a duckling. Both stayed with their flock as it was predation that caused it and both recovered fantastically. They did go through a phase of ugly yellowness like I'm seeing in your wound... but it was just part of the healing (let it scab over) and not actual infection. It looks like heck... but I'm not seeing what I think of as infection (swollen dark red and hot, or puss building which might be easy to confuse with that yellow tissue)... but I am here to learn as well!
I hope your gal pulls through... but more than that I BELIEVE she will!