For bumblefoot - there are some options.
If it's a very early case, you might try rinsing it off, then put triple antibiotic ointment, no painkiller on it, three times a day and especially just before bedtime. No wrapping.
For a further developed bumble, or in any case, you could try the clear (clear, clear, clear, not brown) iodine treatment. Soak the foot for 20 minutes or so (tub time makes this easier - no soap), then drop a few drops of clear iodine on the bumble.
Do nothing else aside from pamper your duck (wink) for several days. Talking, maybe 5 days or so. At that point, most likely there will be a dark scab. Soak the foot again. Try to pull the scab off. If the scab does not loosen easily, reapply the clear iodine, and wait several days again. The scab should then come off fairly easily after soaking, and pull a bunch of yuck with it. If there is still some stuff in there, rinse, reapply clear iodine, wait several days, etc.