The sources you’ve provided, such as usnews.uk and abcnews.chainityai.com, are not affiliated with reputable news organizations. They are known for publishing unverified and often fabricated content. There is no credible evidence or official statement supporting the claim that King Charles III made such a confession.
Official investigations into Princess Diana’s death have concluded that it was a tragic accident. The British Metropolitan Police’s Operation Paget, for instance, found no evidence to support conspiracy theories surrounding her death .People.com
If you’re interested in more information about Princess Diana’s life and legacy, I can provide details from reputable sources. Let me know how you’d like to proceed.