I think the research you linked is for T2D (non-insulin dependent). It's interesting the research into Verapamil apparently is for
both T1 and T2, since my understanding was the mechanism of the diseases were entirely different.
With T1D your body stops producing insulin due to beta cell death caused by an autoimmune disorder, so you need to constantly monitor your blood glucose level and carb intake in order to dose yourself with the right amount of insulin multiple times per day, or you go into hypo/hyperglycemia.
I'm much less familiar with T2D, but I thought the body produces more and more insulin but becomes resistant and the insulin fails to adequately control blood glucose level. Beta cell death in T2D is then a follow-on confounding factor due to the persistently high glucose levels.
Mechanisms of pancreatic beta-cell death in type 1 and type 2 diabetes: many differences, few similarities: http://www.ncbi.nlm.nih.gov/pubmed/16306347