I think you're willfully ignoring what is there, because it doesn't suit your mindset.
The visions had during the Rising Event are the same as any other visions the WoL has. Out of body experience, and then a snap back to immediate reality. They are as real as you want them to be, only that they have no direct bearing on the game's story.
And these were just the immediate examples that came to mind. There are more. The callbacks to the WoLs from 1.0 during ARR. The sidequests with The Wandering Draumaturge. The fact that the WoL has no way to know where to go for quests without us taking them there (this one also meshes rather poorly with the WoL having a poor memory with regards to who's who and all that, but knows exactly where to go, pretty much all of the time). Which leads to the tongue in cheek, often played off of, "Man, you sure do always seem to know exactly when to show up." or "Man, how did you know exactly where to look?" Basically, we give the WoL knowledge they don't otherwise have, all of the time.
I was referencing the very first Final Fantasy and prior entries, yes. The series very often has the concept of fighting with destiny to save the world/a people, and often features time travel, alternate worlds/dimensions, and prophecy.
The Alexander Raids were actually about Alexander manipulating the timeline to stop itself, because it wasn't truly omniscient, and couldn't actually perceive infinite timelines, as that would require infinite aether. It was all a setup for Alexander to contain itself within a static timeloop to prevent draining the world of aether. It has its issues, too. All time travel narratives do.
That's a weird perspective you've got on Elpis. It should be a big stand out, since not only do we go there once, but multiple times, even gaining a useable presence there that does influence the timeline because you see events we're responsible for. Chiefly, Pandemonium. Secondly, sidequests revolving around modern day monsters like the behemoth. Then the rituals, like Nymeia Lilies.
Also it wasn't knowledge of unrecorded history. It was knowledge of purposefully destroyed history.