Hi there, Welcome to BYC!
Could you upload a video of her walking to youtube or Vimeo and copy/paste the link here, so we can get an idea of how bad her limp is?
So it sounds like she has a few problems that need to be taken care of, off the bat I can see the Bumblefoot, it does look pretty bad, I can see her hock joint is swollen in that particular leg which may indicate the infection is spreading to the upper parts of her leg in which case a non-steroidal anti-inflammatory medication will be needed, specifically Meloxicam, Carprofen, or ketoprofen.
In addition to that, a week or two of Epsom salt soaking to loosen the core up, and surgery once after to remove the core may be required, she'll need to be kept in a clean sterilized environment after surgery to prevent another infection, a footpad bandage on the foot, changed every 42 hours, and spraying the wound with an antimicrobial spray would be recommended as well.
When treating Podermatisis (Bumblefoot), the owner must take certain steps to keep this from reoccurring again. Waterfowl are more subject to Bumblefoot when they are kept on hard or rough ground, fed an imbalanced diet, or the birds have another underlying condition that is causing poor hygiene and lack of movement, like a niacin deficiency.
Given that she is a Pekin, I would really not be surprised if she has some deficiency in a B vitamin, therefore I'd probably start her on B complex, and even if the problem is solely related to bumblefoot, treating with B vitamin wouldn't hurt her at all, and actually be quite good for her.
For more info about treating bumblefoot, dosage's, brand's etc, please refer to this thread.
https://www.backyardchickens.com/threads/niacin-deficiency-in-waterfowl.1367557/