Sorry, I remain a sceptic.
Here is their list, noting my own usage:
1. Cinnamon (add to my coffee occasionally and often as a spice in cooking)
2. American Ginseng
3. Probiotics (I regularly include yoghurt in my menu)
4. Aloe Vera (we grow it but don't consume it)
6. Vitamin D (if you are deficient, you need it for health. I have to balance time in the sun with skin cancer but don't take the supp)
8. Magnesium (presently taking it daily for cramps, no effect on my blood glucose)
9. Alpha-Lipoic Acid (have taken it in the past for arthritic pain, but prefer r-ALA, no effect on BGs)
I have tried many but not all in one form or another over the years as noted but not for blood glucose management. I wrote my full response many years ago: Cinnamon, Spices, Herbs and Similar
My summary is succinct and has not changed since: the minimal, if any, effect that cinnamon had on me was trivial. Reducing my carb input by just a few grams had a much greater effect.
I reckon that applies to all of the above.