So are you saying that each of these "experts" is not an actual top of field expert but merely one of hundreds of expert cogs (per field!) in a giant machine so vast that of course some of them will crashout, be kidnapped, blackmailed, die outright, agree to a global government psyop, etc? But that's so much less fun, especially when you consider the espionage angle.
I believe the probability to die or get missing for a middle aged person is extremely low.
So no, it's not expected that "some of a group of 5.000 Persons" would die or go missing.
Not even expert cogs, only 6 of the 11 are scientists or engineers