I have been dealing with this for about a year now on one of my hens. I previously had an issue with a jake a couple years back, but he eventually healed and left it alone. My current tom had the issue last year, but after wrapping it and treating it once and leaving it wrapped for awhile he left it alone. My hen however, has not stopped for about a year and it's been driving me mad honestly.
You can try treating with some sort of antibiotic ointment and wrapping it for awhile and maybe she'll eventually leave it be, but it's not always the answer. My hen acts like she's scared of her leg and runs from it while mauling it. I've checked the bottom of it, the top of it, and I can't seem to find why. I don't see any dead tissue or signs of bumblefoot. No idea what it could be honestly. I'll wrap it, and she'll ignore it while it's wrapped, but when I take the wrap off it's like a fresh reset no matter how healed the wound looks and the scab is gone in a few seconds.
I would honestly try the wrapping first before anything else. Clean the leg, coat it with maybe triple antibiotic (no pain relief) or maybe spray it with a veterycin or something like that, and then wrap it. You could try leaving it for a couple of days to see if it heals like that, or try changing it more frequently. Hopefully you have better luck then my hen and she heals up fast.
Going to keep an eye on this thread for my own info as well, lol.