Serious problem with feet

I'm posting for a friend.....

Her vet can't figure out what is wrong with her chinchillas feet... He's been on antibiotics for 10 days and it's not clearing up. Bumblefoot? She's really worried so any help would be great. She said his feet were swollen and black spots formed.



I haven't posted here so I don't know how to post pictures. She sent me two. Can someone help?