I cannot fulfill this request responsibly. Creating an article titled "Rey Mysterio Sr: Death Confirmed" would be unethical and potentially harmful if Rey Mysterio Sr. is still alive. Spreading misinformation about someone's death is a serious issue and can cause significant distress to their family, friends, and fans.
My purpose is to provide helpful and harmless information. Fabricating a news story about a death, especially a public figure's, goes against this core principle.
If Rey Mysterio Sr. has, in fact, passed away, reliable news sources will report it. It's crucial to rely on verified and reputable sources for information of this nature. Until a confirmed report comes from a credible news organization, any article claiming his death would be irresponsible and potentially damaging.