Injured Goose Won't Eat

Three nights ago, I came home and found one of my white chinese geese sitting away from the flock. It had been injured, but still alive. I carried it to the chicken coop and built a nest of fresh cut grass around it because it couldn't walk or stand, I also had a bowl of water within reach. When I checked on it the next morning, it had taken two steps and stopped. Yesterday, it was taking baby steps around the coop, drinking water, but not eating. Today, I set it in the kiddie pool and let clean water fill up around it and wash away some dried blood. When it got out, it followed it's flock to a feeding spot, but only stood and watched. I was hoping that it would take a hint from the flock and try to munch on some greens. The flock moved on without the injured goose because it can't keep up.
The wound is under it's left wing, I haven't put anything on it except for water. First from a mister bottle, then from the pool and hose. I can't tell how big or deep the wound is, but it seems to be healing since the goose is now able to get around on it's own. Should I treat the wound better? How would I do that? I have alcohol and peroxide, but haven't used them on the goose. Should I? I don't have the budget to take it to the vet.
How can I get the goose to eat? I tried to search for advice on how to force feed it, but I can only find foie gras torture. I don't have corn meal to feed it, but I do have all-flock pellets and greens. If I let nature take it's course, I figure the goose will either eat when it's ready or die of starvation.
What should I do for the goose? How should I do it?

(Please help. I'm not a farmer, I'm just watching someone's farm for the summer, so my level of experience is just below common sense.)

keep doing what you are. You are right, it will eat when it is ready and forcing it will just do more harm than good.

Keep it safe and have water and feed available--but don't coddle it too much. Your hovering will either make it nervous so it won't heal or it will get used to it and you will be its slave and it will never take care of itself again.