My recollection from viewing it on a phone. I was going to look at it closely on a PC when i got home but it is now gone. The below is what I remember but i was looking on a small screen and this was written from memory so it could be wrong....
The video was an over the shoulder view from the front seat of a tandem 2 seat glider. They were ridge soaring by the looks of it about 3000 feet AGL above the valley, though that is estimated from my memory. There is considerable cloud build up, about 3/4 or more sky coverage, though the valley looked more clear, and they were above the cloud base and about level with some of the tops the clouds. Some clouds were also higher. There was some discussion between the pilots about locations/landmarks and the conditions ahead and about having final glide to somewhere but another few hundred feet being better. They were in ok lift and it increased slightly however they were now above the cloud but only just. Initially they turned to the left, and the lift became sink. [I think they had been blown down wind behind the ridge. To get back to the lift they needed to turn to the right but that was now into the could]. They turn left and the glider goes into the cloud and all is white, They lose control(possibly spin though not sure) and speed builds (My opinion by the sound) and the white outside view becomes very green with a glimpse of the hill/ground. A fair bit of shouting and then they recover, the camera is knocked to an odd angle and we don't really get a good view for the remainder. In the audio these is panicked talk about their orientation and who has control. Then after a few more seconds there is a call of spin, spin and they have what looks like an incipient spin. The video ends with the glider recovering from the spin, at low level, downwind of the ridge. The ultimate fate is not shown.
Nobody.