Hi Emily, you said at first that you were going to take her to the vet... did you end up doing that and what did they say?
I'm not an expert by any means, but my thought is that if the entire foot, toes and leg were swollen in the beginning that would imply infection... possibly stemming from that bumble that was on her heal. Depending on what your vet said/says, you might look into trying antibiotics. If you do, you should supplement her diet with probiotics.
As far as additional special treatment goes (epsom salt soaks, wraps, etc.), do what you're comfortable with. I personally take a hands-off approach when it comes to sprains/pulled muscles, for example.
And it's always best to give your duck enough time, they are very willful and determined to live... they can completely turn around from injury or disease. The way you've described it here, it sounds like your duck has improved since this all started. So she might have a hold of whatever is going on and just needs more time. Of course, you know the situation and the duck much better than I do, I just wanted to share my thoughts.
Wishing you the best.
