Ok so hear me out. In TMP the Magnus Institute burned down in 1999. According the TMA wiki's timeline, in 1999 "[a] number of the Magnus Institute's files are leaked to the press, causing widespread derision," citing MAG 68: The Tale of a Field Hospital. Now I haven't re-listened to that episode yet, so I don't know exactly what it says, but isn't that curious? In the TMA timeline in 1999 something big also happened, sure not the institute burning down, but maybe they could be related? Iirc, the two series are in alternate timelines? Or something like that? The fire/press leak could be the divergence point. Maybe Martin and Jon after being dissappeared at the end of TMA ended up in this alternate timeline, and that's how we got the text-to-speech voices. Since doing the ritual was supposed to doom some other timeline/universe/world.