I think the problem is that if you can't fix whatever is causing your body to attack your own pancreas first, it doesn't really matter if you're able to slowly regenerate the insulin-producing cells - you can't make any headway.
The article hypes increased beta cell generation but as far as I skipped doesn't address the characteristic T1 immune response attacking them. Seems incomplete to me.
If the immune response is stalled/reversed during the fast, the causal agent seems pretty clear (and corroborated by studies innumerable): it's the food you eat.