For a single hit to take out both and engine would be a golden bullet as the nacelles and fuselage protect any critical point. As the V-22 travels so much faster this is really extremely improbable (not the extremely improbable that Sikorsky used to explain the S-92, but a real one).
On the Chinook you need not only to only hit one gearbox or the shaft, but can have total loss from a seemingly minor event (initiated by a chip light):
Daily Union - Google News Archive Search
As most who died were parachutist many lives could have been saved by ordering an immediate evacuation instead of trying to return to the field.
The Sultan