My knowledge of midazolam is limited. Propofol is the most dangerous of the anesthetics used for induction of anesthesia such as etomidate, thiopental sodium, and ketamine. Even the standard induction dose stops breathing. I have never read about the mechanism of action of midazolam.
I assume you have a procedural sedation. Is this an endoscopy or a colonoscopy? I don't know the criteria for the statistics you mention. What I do know is anesthesia is easy, sedation is difficult. From what I have read, patient satisfaction is higher with propofol in procedural sedation than with midazolam. I think the therapeutic dose required for depth of sedation with midazolam is very precise. This may be what makes it deadly. I think propofol is a good choice. I don't know if the statistics include cases of sepsis. Since propofol is an oil emulsion, it carries the risk of sepsis. I've read news of people dying from sepsis due to propofol in my country.