[Oh, well, that's new. By which she means that's not precisely new because she'd pretty much already figured that out for herself, but independent corroboration works wonders in her book for letting her actually believe something. Johto and its inhabitants had started out pretty firmly in the "impossible" range of her believability scale, but more and more the evidence is pushing that toward "improbable", instead.

And of course, even Sherlock Holmes was willing to concede that once the impossible was eliminated, even something improbable might be the truth.]

So it's a nexus theory. One central location at an intersection of many worlds overseen by some power capable of bringing select people from those many worlds to that single point in time and space.

[...Kirigiri.]

If that's so, then we should be able to find either the person or the apparatus responsible for drawing people here.