Journalism is not in a good place these days, to put it mildly, so you're going to get a lot of low-effort reporting and clickbait. Some facts might emerge in the trial of the killer, especially if his girlfriend agrees to testify against him in exchange for leniency. Also, any digital communication between the killer and the victim might come to light in court. You just have to wait.

My classic example of this is the Duke Lacrosse case back in 2006. A black woman accused white athletes of sexual assault, and everyone piled on with the perceived underdog against the privileged athletes. But then, as the case progressed, it all fell apart. It turned out the accuser had lied, and, even more, the district attorney prosecuting the case was eventually himself charged with criminal misconduct for attempting to suppress evidence and disbarred. The accuser later went on to kill her boyfriend.

Whenever I feel like jumping to a conclusion on minimal evidence because it fits some narrative, I take a step back and remind myself not to get ahead of the facts.