The obvious question is, how did anyone know the aircraft were contaminated ?
Was it a case that such testing was relatively common yet obviously not at advertised times for the West, explaining a team with geiger-counters whatever being handy ?
I realise we live in different times now, but I shouldn't think any passengers or indeed crew would be too chuffed at being routed in such a place, if no alternative then I suppose abandoning the route would be a form of blockade acceptance.
OR did the aircraft ' just happen ' to be carrying sensors of the monitoring & intel' kind ?
It's not exactly unheard of to use airliners -some perhaps most full of innocent passengers - for intel' purposes, I know an (ex ) RAF photographer who at around that time would be a ' passenger invited to see the flight deck ', where he would don overalls & ( large hand-held )camera to film underneath the aircraft as it ' got lost '...
One of the possible results of such practices being the shooting down of the Korean Airways 747 when it strayed - and why is still a little hazy
AFAIK - near the very sensitive Kwajaleen ( sp' ? ) Peninsula a while ago.