You are doing the proper post-op on this and she should recover. But the next time you have a chicken with Bumblefoot, and for anyone else reading this, please order some Tricide Neo and follow the directions. I have used it on four different chickens over the past 4 years, and all have recovered, and recovered quickly, from Bumblefoot. It's an antibiotic that you mix in water, then your chicken gets a 10 minute footbath daily for several days. And the spot will clear up quickly.
I have a few posts here from 2017 on this treatment, and there are other members who have used this successfully. It's still fairly new, but can be found from several dealers, usually Koi and Goldfish companys, since it was developed for treatment of fin rot, which is the same bacteria infection that we deal with with Bumblefoot. The only drawback is that the solution cannot be kept in storage, since it breaks down quickly. You mix it, use it for the course of treatment, and then throw it out. But it beats trying to do surgery. And every chicken I have used this on quickly decides that a warm foot bath is pretty darned nice. They actually enjoy it.