Tetra Corp / Formula 3 Treatment for Nail Fungus with 100% money back - no refund Eaton Rapids, Michigan

I have a nail fungus for years. Seen doctors who all they want to do is give me pills for my condition with many side effects.
So I made an appointment with Dr. Mitnick a Podiatrist. When I went in he looked at my nails and said to use Formula 3 and charged me $75 for the visit and $45 for Formula 3. I was happy for the moment as the doctor said the manufacturer has no questions asked refund policy.
On his web page he states: No Proof of Purchase- all you will have to do is tell the company from whom you purchased Formula3 (Marc Mitnick DPM) and what you were charged. Thats all!
When I got home I showed the product to my wife and she said the product she had seen the product where she gets he nails done. She called and said they sell the same product for $15.
Then when you read the label the product states not effective on nails.  So I called for a refund. I was told the check would be sent in a week. 3 weeks later no check. I called again and got a run around. Still no check/refund. So I called my Credit Card company and had the charge removed.
According to the company www.tetracorp.com Formula 3 sold on the internet is outdated or mislabeled. You see the product all over the internet so not sure what to think. Seems like a scam. Nail salons selling for $12 and podiatrists (I have been told they are not real doctors) selling for $45.
I asked my doctor about this and he simply said that anybody in medicine knows nothing works 100% of the time and it sounds like some con as he has never seen a study or medical report on a treatment for nail fungus that shows 100% success.