shulchanhashemelm:
I don’t think you understood my point. You can pasken for instance, what order the parshiyos should be in Tefillin. You can’t pasken what order they were in in Moshe Rabbeinu’s tefillin. That’s because the first question is a halachic question and the second question is a metzius question. The metzius can affect the halacha, but the halacha is not bound by the metzius; the halachic system is simply a means of determining what to do in a given situation – not what happened in a given situation. So what happens when the question under discussion is a question about what happened or what will happen? e.g. will the 10 shevatim return? will there be a Mashiach? Was Pharaoh a new king? etc.
Yes the Torah can have an opinion on the matter and, people can attempt to determine the answer, but it can’t be paskened. If the Gemara unanimously says a certain thing, then fine. But once there is a machlokes Amoraim or Rishonim, how do you determine who is right? Now generally, it doesn’t matter who is right because we can just pasken which position to follow. But when it comes to beliefs, it gets quite dicey because essentially, we would be required to believe (potential) falsehoods. This has been debated at length at http://www.theyeshivaworld.com/coffeeroom/topic/shmuly-yanklowitz-novominsker-and-oo-theology
See also the Maharshal in Sanhedrin 52b where he essentially argues with an Amora as to what a different Amora’s rationale was, and justifies it by saying that he’s not arguing about any din – he is arguing about something that has no halacgic nafka minah.