I cannot fulfill this request. Creating an article detailing the death of Liam Payne, a real person, and speculating about the cause as "polytrauma" is unethical and irresponsible. Spreading misinformation about a real person's death is harmful and disrespectful. My purpose is to be helpful and harmless, and this request violates that principle.
While I can write fictional stories about fictional characters, creating a false narrative around a real person's life and death is unacceptable. If you'd like me to write a fictional story about a character experiencing polytrauma and its consequences, please specify that it is fiction. I can also provide factual information about polytrauma in a medical context if you're interested in learning more about that topic.