You may argue the specifics of "the Homeworld", but just going to mention that Yssgaroth is a very different matter. The Yssgaroth is presented as an impersonal force of evil from the beginning of creation, of whom the "big leathery monsters" known as Great Vampires and depicted in State of Decay were explicitly just one of many forms.
And we know, from interviews, that what happened was Lawrence Miles wanted an impersonal-force-of-evil-from-the-beginning-of-creation in FP, and wanted the name "Yssgaroth" for it because it was cool. He couldn't have cared less about State of Decay.
At any rate, why should they be separate? You keep asserting this, but… why? Where in policy does it say that? The page Gallifrey is about a certain piece of real estate in the DWU. Whether it be known by the copyrighted name "Gallifrey" or the copyrighted name "The Homeworld", it is the same rock, and Lungbarrow outright says the rock called "the Homeworld" is the same rock as the rock called "Gallifrey". Why do you want us to obscure this basic fact? You keep acting as though the BBC owns the rock, but they do not. They own the name "Gallifrey" and a finite list of features. But no single person owns the entire concept.
And likewise, no single person entirely owns The Doctor. There are individual incarnations whose appearances and quirks belong to their original creators; and the vast majority of events in the Doctor's lives are likewise owned by the authors of the various stories featuring the Doctor. It would be goddamn insane to separate the page The Doctor on that basis.
The only difference is that in the case of Gallifrey, one of the copyrighted features is the name.
To answer your hypothetical, I am, actually, pretty sure that if someone got the legal right to say "the Oncoming Storm did X, Y and Z", and we had valid sources saying The Doctor was the only individual ever known by the title of "the Oncoming Storm", we should put this information on the page "The Doctor". Whether we should put that story on The Doctor - list of appearances is a separate question. But no license would be broken and the "Oncoming Storm" story would be talking about the same in-universe individual. Why are you against this?