Here is an excerpt about forced molting. I know it is not what you are trying to achieve, but it gives some pertinent information regarding dietary needs and tolerances of chickens.
How to Basics in Forced Molting Layers Force molting is a technique that forces the layers to change their feathers. In this process, the layers stop laying eggs for about a month in preparation for a bigger egg production in the following months ahead. After force molting, the layers feathers become shiny and the eggs have thicker shells.
Forced molting is very simple to do. Layers that have to undergo force molting should be 9 to 11 months old. If they are older, they might not be able to endure the torture they have to undergo. For 12 days, the birds are not given any commercial feed. They are only given water to drink.
On the 13th day, the birds are each given 10 grams of feed. This is very small since the normal diet of a layer is 110 grams per day. On the 14th day, the birds are given 20 grams of feed. On the 15th day, they are given 4o grams of feed. On the 16th day from the start of forced molting, they birds are given 80 grams and on the 17th day, full feed of 110 grams is given.
I do not condone the practice of starving birds to force a molt, but in this case you need to know what a chicken can tolerate. 110 grams of feed/day is the recommended daily feeding, so if you could give her that (or less) in two feedings (a.m. and p.m.) maybe she will be able to rest enough to allow for some healing to occur.
Your other option is to take her to a vet and have a purse stitch put in for a few days. A very expensive and not always effective option, but I thought I'd throw it out there.