Really glad you can smell it on people, smell is a powerful diagnostic tool that few people are trained on.
At the hospital, I saw a gastroenterologist who specialized in Celiac, because I had just been diagnosed with Celiac a year earlier and many of my symptoms seemed related to digestion. He absolutely should have done diabetes tests. On the last day of the 2 weeks I was there, he said "It could be type 1 diabetes... some people get that too" but didn't order any tests. When I was diagnosed at the ER another year later, my glucose was 650 (very high) and had been averaging 300 (it should be ~85). So yeah, the doctors were negligent, in my assessment.