This is the report from the local Marlborough Express. The pilot and passenger are not named. Lucky escape from glider crash south of Blenheim
It would seem that the wing failed and folded over as it is seen on the ground. This prevented the ballistic parachute from being deployed & the glider then spiralled down like a sycamore seed as Pylon said about 1500 feet. They were very lucky & I bet extremely dizzy on contact with the side of the mountain.