This smelled fishy to me so I looked a little further into the numbers. The page linking to the study says that it involved 1,000 insured participants and 1,000 uninsured. So right off the bat, unless exactly 50% of the population is insured/uninsured, you can't really extrapolate exact numbers from this survey, unless they gave you results broken down by insurance status.
According to https://www.cdc.gov/diabetes/data/statistics-report/diagnose..., about 46% of diagnosed diabetes cases are in people >65, meaning covered by medicare. I'd assume that at least a good chunk of people <65 have insurance, meaning this survey is completely unrepresentative from the start.
Don't take any of this to mean that I don't think the price of insulin is too high. It certainly is. But this survey is misleading at best.