Why would Revan visit Kreia in the Trayus even were he aware she was there? If we accept the theory that Kreia is Arren Kae, Revan has every reason to stay away from her, considering he murdered her lover. Even if Kreia is not Kae, Revan would not have any reason to interact on pleasant terms with a Sith Lord, for as Kreia herself notes, she did follow the Sith ideology, even its ruinous aspects, at this point.

I don't have access to all the sources the fansite's owner used but when Kreia is discussing Revan, she says:

Kreia: I do not believe the Jedi Council changed Revan, as they claimed. They merely stripped away the surface, and allowed the true self to emerge again - someone who was willing to wage war to save others. But that is my belief, since I knew Revan from long ago... as a master knows their apprentice.

Kreia: He came to me, yes. Both before and after, before Revan knew himself. And after, in the times when Revan was coming into his own and learning he was more than he had been told.

In the Trayus core (using male pronouns for Revan even though the video refers to a female Revan):

Exile: And Revan? He came here, was here. What happened to him?

Kreia: He came because he remembered what laid buried here - this place, its teachings. The remnants here paved the way to Korriban. And he came because Malachor, like Korriban, lies on the fringes of the ancient Sith Empire, where the True Sith wait for us, in the dark.

[...]

Kreia: Revan knew the true war is not against the Republic. It waits for us

Katarr's destruction occurred years before the events of KOTOR 2

Wookiepedia places Katarr's destruction at 3952 BBY (from the book Jedi vs. Sith: The Essential Guide to the Force) and Kotor 2 takes place in 3951 BBY so only a year has passed.