I wonder if she started walking like that because she was in a lot of pain with both sides? In my experience, that bumblefoot needs to be wrapped up at all times. If you don't keep it wrapped, germs are constantly being introduced to the wound. It might take a little while for her to learn to...
Are you keeping her foot wrapped all the time?
Did you notice any improvements in her foot or leg while she was on the sulfa Rx from your vet?
Any other symptoms with her? Does the swollen leg feel warmer to the touch than the other? Is it soft or more hard?
I'm hoping you don't mind answering a few more questions. I've been looking at the pictures and video you posted of Holly and I've got several things going through my mind but I just wanted to ask these things. Is the initial bumblefoot that the vet operated on, the same bumblefoot that's going...
I don't remember the one I've used in the past. It'd be a good idea to ask your vet if she has a good one in mind. I'm thinking about you and your duck 💜 She's in good hands with such a caring keeper.