I suspect that diabetes in ME is different and related to the disease. I can't keep to a particular diet, I am just too ill. Instead I have always ate the recommended healthy diet, as unprocessed as possible, limited empty calories.
I used to get hypoglycaemia if I did not eat enough carbohydrates which I now know was because my dysautonomia meant the signal to release the necessary glucose was not being sent to my liver in time. It is very reasonable that this caused a burn out of my pancreas cells. As my blood sugar levels are now slightly higher all the time I no longer get the hypoglycaemic attacks which makes life easier!
Things which help normal people may not be appropriate for people with ME. Just like we can't take up walking to help high blood pressure our diabetes may not be the same or respond the same as it does in trials of healthy people.
Anything, diet or whatever, that helps an individual with ME is good but it is not easy to relate our experiences with those of the healthy world.