Morrowind's in-game texts do not offer a single creation story. They offer several that cannot be reconciled, and the design treats that friction as the point.
The Monomyth lays out the split between Anu and Padomay and the resulting et'Ada. The Battle of Red Mountain and the notes on the Tribunal's rise give different sequences and different motives for the same deaths. None of these sources are presented as false; they are simply allowed to stand beside one another.
The effect is that the world does not run on a fixed historical record. It runs on which version enough people treat as true. When the Nerevarine fulfills prophecies drawn from competing traditions, the act itself strengthens one account over the others. The player is not confirming a pre-written history. The player is supplying the weight that makes one version more real than its rivals.
This is visible in the handling of the Heart of Lorkhan. Vivec's account, "The Battle of Red Mountain," explicitly gives the Tribunal's self-justifying chain: preserve Kagrenac's tools for Chimer welfare/security, Sotha Sil studies them, then the Tribunal use them after embracing a vision of a better world.
I have not seen a later title repeat this structure with the same consistency. Later games tend to resolve contradictions through additional lore rather than leaving them active. Morrowind leaves them active on purpose.
The Prisoner therefore functions less as an observer of mythic time and more as one of its maintenance mechanisms. Belief is not flavor text. It is the load-bearing element.
Which of the Red Mountain accounts do you treat as decisive when replaying, and does that choice change how you read the Nerevarine prophecies?