Has anyone cultured the area? Stay off the cream for at least a few days, and ask them to do a culture.
It's not a herpes sore - they wouldn't last this long.
Were you tested for syphilis?
It could be a fungal infection, and not responsive to Ketocozanole cream. You shouldn't be on it for that long, especially with no response.
There are all kinds of bacteria - non-STD bacteria - that can cause skin issues, like staph, etc. You need to get a would culture and find out what's happening here.