This is a great testimonial but it is not a legal cure until he has been cancer free for 5 years, which was not brought up. It was also not pointed out what the specific skin cancer was, which does make a difference.
It is good that it worked for him and I encourage some official studies to verify this effect.
I could have made the same claim for another product that I used for my diagnosed skin cancer ( basal cell ) and I have been verified cancer free for almost 8 years now.