Or, as known in any large ORGANIZATION, That's the BOSSES ORDERS!
A lot of people in the know? Not really. Just people going along with (DO AS YOU ARE TOLD). Also people going along because they are sure it is the RIGHT thing to do.
RISKING A LOT? No, not really. Since none of them had to be told to do anything specific, they can't be found guilty of anything. So they made a mistake, a miscalculation, a misjudgement. OOOOPS !
WHY WOULD THEY DO IT? Same reason the HANG DW crowd ignores any evidence, testimony that shows DW might not be guilty.
THEY ALL BELIEVE ! TOTALLY COMMITTED BELIEF!
They are just finding evidence to match their belief.