One of the kids on the island was actually polish-norwegian. He gave a huge interview for polish TV. He said he had gun at his head and begged for his life, with every other people around him dead. The killer spared him. Actually it was him at the very first pic from the island that you posted on one of the first pages, with the kid in the water and the killer aiming. He also said that later the killer got to his place again and he was faking death that time. The shooter shot him in the arm to check if he's dead. He was terrified enough to not move after getting shot.
He also talked about 10 years old boy that have seen his father getting killed there. The killer then wanted to kill the boy but he started telling things like "I'm too young to die, go away, leave us alone" and he was also spared.
This shit sounds like some teenage slasher movie...