I would definitely try to get her into the vet. If they are booked out that far, you might ask them if they know of any urgent cares that will see chickens.
For Candy (who had two rough puncture/tear injuries), the urgent care vet was able to clean the wound (debriding) and then gave me some silver cream and a short course of antibiotics.
And while this may not be 100% how it's supposed to work, if you email your vet pictures of the injuries, they might be willing to let you come and pick up some cream.
As for feather trimming, I haven't done much of it. Someone else can advise you on that part.
If you can get hold of saline spray, or if you're using betadine/iodine, it's probably worth doing at least one more really good rinse out, then rinse with saline once or twice a day until it crusts over.