But then if we're doing age ranges, the 10 people "tied to sensitive research" who have disappeared or died are 59, 61, 60, 68, 53, 60, 78, 47, 67, 39 (with the two youngest identified as homicide and suicide). How does a cohort with an average age in their 60s compare with the age range of actively practising researchers?

I should imagine you could look at the CDC data for those cohorts and perform the same kind of analysis as he has.