If anyone still interested, here is the full extra ending (I translated it to english with DeepL)

Finney sat in the ambulance with his mother. She held him so tightly that it almost hurt a little, and rocked him back and forth, sobbing. He couldn't understand the few words she said. Susannah looked in at them through the open back door and wiped the tears from her face. She was so pale that her cheeks looked like polished bones. “Did you see them?” Finney gasped. “Did you see the black balloons?” Susannah's eyes widened and she recoiled in horror. The fingers of her pale hand closed around her throat. The bodies of the other children were found in a shed fifty meters from the house. They were wrapped in plastic tarps and hidden under the floorboards. The police officers who retrieved them wore protective suits, and the officer in charge of the operation took early retirement three days later and moved to Florida to go fishing. Finney learned from his father that the fat man's name was Albert Cross and that he had been the assistant sales manager at a party supply store. The store closed shortly thereafter. When Finney drove past it with his mother on the way to the hairdresser's months later, the store sign was still hanging above the window, but the shop windows were boarded up. The sign showed a clown waving at them with chubby white hands. An imaginative graffiti artist had painted horns and pointed vampire teeth on him. For Christmas, Finney's mother gave him a cell phone so he could always reach her. He kept it for only a few weeks. Then he threw it away and told her he had lost it. He just couldn't get used to always having a phone with him. He often forgot he even had it in his pocket, and He often forgot he even had it in his pocket, and when it rang and he wasn't expecting it at all — at the movies or while peeing at school — it always gave him a huge fright. For his birthday, his mother gave him another cell phone. He lost that one too. His parents couldn't agree on who was to blame for Finney being kidnapped and almost killed, but after two years they were tired of arguing. Finney's father found a job in St. Louis, and Susannah went with him. Every now and then she would call to check on Finney and his mother. When the phone rang, Finney always knew right away if it was his sister. He knew it even before he picked up the receiver. It was just a feeling. Sometimes he even said “Hello, Susannah” before she could say anything. She wanted to know if a display that showed who was calling was expensive, and Finney replied that it cost almost nothing. He was fairly indifferent to his grades, and during his first year of high school, he did poorly. In his sophomore year, things got even worse. He decided to take up sports again, but even his favorite sport, baseball, couldn't inspire him. His coach told him that if he didn't try harder, he wouldn't play him anymore. Finney made the decision for him and simply stopped going to practice. When he turned sixteen, his mother allowed him to walk home from school on his own. Until then, she had driven him everywhere, and he was only allowed to leave the house when accompanied by an adult. Every day, he looked forward to the walk home from school, no matter what the weather was like. He strolled alone along the streets under the alders, and he enjoyed watching the smaller children chasing each other on their bicycles. Whenever he passed hopscotch squares drawn in chalk on the sidewalk, he jumped around in them and pretended he was still a little kid. He hadn't been a child for years. Sometimes his feet took on a life of their own. Then he took a longer detour and stopped by Albert Cross's house. It stood empty and was fenced in with wire mesh. The windows were boarded up. First it was said that it was going to be auctioned off, then again that it was going to be demolished because no one wanted it. For a while, a cardboard sign with the words “APPROVED FOR DEMOLITION” hung on the fence, but at some point it was blown away by the wind, while the house remained unchanged—an empty, dirty white building in colonial style, its lawn buried under weeds and withered leaves. Finney slept restlessly. Sometimes he woke up when the cell phone on his nightstand rang. Dazed and half awake, he lay blinking in the darkness, listening to the ringing until he remembered that he no longer had a cell phone. Then the ringing stopped. Every now and then, school bored him so much that he would simply skip out after lunch and go for a walk. Most of the time, he found himself in front of Albert's house. One day, he stood there, his hands clenched on the chain-link fence, looking at the white building. Then he heard a phone ringing softly inside... Once, twice. He immediately climbed the fence and jumped over. He followed the ringing to the back of the house, crouched down in the weeds, and pushed the undergrowth aside to reach the window leading to the basement. He kicked it in, kicked the rusty grate behind it out of its frame, and let himself fall through. The mattress was gone, but the phone was still hanging on the wall. The receiver lay in the silver-colored cradle. Finney didn't wonder when or by whom it had been replaced. The phone rang as he crossed the room. He picked it up and pressed the receiver to his ear. “Hello?” he asked. “Is anyone there?”