Joseph, you should talk with your doctor or diabetes educator about this. In general, you can take metformin with most herbs, but your case might be different, and you might not need to. You might have to experiment. The same with insulin, although you have to be more careful there — in all cases you should work with your doctor or diabetes educator.
If you google “diabetes cure” you are directed to websites like WebMD and the Mayo Clinic where you find information on diet, exercise, medication, and insulin therapy, but nothing about the cure. This lack of information may have to do with the fact that Americans spend $322 billion a year to treat diabetes, $60 billion a year on weight-loss programs, and $124 billion a year on snack foods. This is about 3% of the US economy! Because so many peoples’ livelihoods are supported by diabetes and its main cause, obesity, the viral effect of people getting cured and telling others is greatly diminished.