I would say that as a rule, it's intentionally left ambiguous whether the Nerevarine did all quests not related to the Nerevarine prophecies (i.e., all quests not part of the original main quest, and presumably Tribunal as well since it is necessary for one to be the Nerevarine for its story to work.) so that players can decide for themselves based on whether they did it in their game. So maybe the Nerevarine took one of those positions or the other, or maybe not, it's all a matter of choice, I think that's what we should conclude.
And I agree with this completely, save one thing. If evidence that the (Hero) played a role in any side quest is presented
In official content, that does cannonize the event, at least until it is retconned. It is up to the writers of the lore to ensure that the (Hero)'s Gender/Class/Race/Birthsign is left unknown, for the sake of the players.
Again, this is just my Opinion, and is in no way the right or wrong answer. I post it only for the sake of debate, as well as defining my logic.