When the son jumps out of the ski lift, he throws his backpack down too, when he skies a few seconds later the backpack is not on his back.
After jumping out of the ski-lift Rein meets up with the rest of the group at 'Adi's' berghütte, in the Swiss Alps. His father Gijs is already having a beer. The beer glass he has been served says 'Lasko', which is a Slovenian brand and gives away the filming location. Although not impossible, it would be very unlikely to get Lasko draught beer in a Swiss mountain hut.