I don't think the author and editor of that headline wants the wording to be taken literally, believing it to be supernatural and outside the realm of causality

I don't think the author and editor of that headline wants the wording to be taken literally, believing it to be supernatural and outside the realm of causality. Instead, what they're trying to drum up attention for in the headline is that it can be explained, but only by the activity of a previously. unknown force, astronomical phenomenon, planet, or other new and interesting potential discovery. Such as aliens. The headline should read "... is unlikely to be caused by existing models and behavioral simulations of the solar system", but that's less likely to get clicks. That, or "Discovery of A New Retrograde Trans-Neptunian Object: Hint of A Common Orbital Plane for Low Semi-Major Axis, High Inclination TNOs and Centaurs", which is the title of the backing paper.