I don't have any experince with them. I am sure the Christopher books or CD have the answers, Dr. John worked on all human ailments. I took a quick look at their general ailment list and corns are not listed. They have a master CD that has everything Dr. Joh ever put on a piece of paper and in there you can find just about anything. I don't have it where I am at now.
I would suggest all the general cleanses in the 108 page book and throw away the socks and rarely wear shoes if I was her. I would apply cayenne to the bottoms of the feet and work on geting the kidneys clean. I like the leg shaker machines or people call them chi machines, i would use one 30 minutes a day.
I would try some cancer salve on the worse one and see what comes out.