Vedda Blood Sugar Remedy - Scam??

Has anyone here heard of the “Vedda Blood Sugar Remedy”?? It’s supposed to be based off of a tribe in Sri Lanka that has like, no diabetes/blood sugar problems because of this miraculous diet. My dad (Type II) is currently obsessed with it. He’s already spent $30 on the PDF and was raving about how he wants to buy more bonus material. When I poked and probed, I found out that he was hooked on this amazing cure for diabetes after seeing an ad on it. I’ve tried to research it online but all my Googling has come up with zero tangible evidence. There are some “testimonials” on them, but even the few supposed independent websites reviewing it just don’t seem legit and use more or less the same words.

It sounds (and feels) so sketchy and scammy, but I have no proof, just a gut feeling which I know won’t fly when I try to tell my parents not to throw more money at this random website. Help!