Not bumble foot. A video of him trying to walk would be very helpful.. have you had snow and ice where you live?
I presently have one duck in my hospital room who has the same symptoms you describe, and what happened to her was she slipped running on icy ground that was uneven. At first, I thought it was her hip joint because she wasn’t moving any of her leg just hopping on the other foot and dragging the injured leg behind her. I put her in lukewarm Epson salt bath soaks and gave her liquid Bcomplex one ML daily. Also giving her glucosamine chondroitin, and meloxicam for pain. She was not eating., so I had to start tube feeding her, which actually made it easier to give her the medication’s mixed in with the soupy feed.
I did this daily and after a few days I noticed she was able to move the top half of her leg but not her foot at all. My best guess was that she sprained the foot perhaps all the way backwards. I could not really see any swelling anywhere when I examined her and re-examined her daily, but I do see a little discoloration in what I guess we would call the ankle joint where the foot connects to the leg., so I ordered a foot brace, but it took 10 days to arrive. In the meantime I kept giving her some swimming time in my bathtub each day in lukewarm water plus tube feeding her twice a day and giving her the medication’s and supplements. And oh I forgot to mention I also added 1/2 ML of rooster, booster, poultry cell or nutridrench once daily. But I tube fed her twice daily and gave her a snack of handful of peas in a small dish of water and at first, she only ate one Pea and then after a few days she ate a few peas and now she eats several peas.
Did I mention that I have a friend duck in the hospital room with her at all times? I have been rotating different ones of her friend Ducks in and out of hospital room to be her companion.
In the meantime, about six days ago, the foot brace came and we started using it, now she is slowly adjusting to it, and starting to use it a little bit for balance when she is standing still, but I have still not seen her taken actual step with it. She’s been hopping and or trying to fly to get away from me when I go in the hospital room to pick her up to tube feed her.
We will see how she does and I will let you know it has almost been four weeks since her injury was January 19. If you have any questions or want to try any of these things, I can give you more information even pictures. For example, here is the liquid be complex that I myself and many others here recommend
And here is how to give meds to ducks
(BRB I have to finish this post and start another one to go and get the link first)