Religion is a means of finding the Truth about ourselves, just as Science is a means of finding the Truth about our Universe. Science has limitations, despite being incredibly useful, in other ways. And Faith-based systems have them, too. For one thing, unlike Science, it's entirely subjective, but that's what we want. So, Chakotay's Vision Quests can't really about Life unfolding its unsolved mysteries that he wasn't even aware of, yet. Not at all.
What they're about is helping him with navigating through current challenges and uncertainties that he's experiencing and directly exposed to. And that means that he's always, at least, partially in control of his own Vision Quests, even if it's at the subconscious level. So, playing the Vision Quests as though they're open to interpretation, as opposed to being an absolute, is entirely appropriate.
They're not really about being given direct and obvious answers as much as they are about unraveling knots. In Chakotay's mind, he's stuck somehow, somewhere ... he's snagged on some issue, unable to just move on from it, entirely. A full, qualified answer isn't really necessary to do that. Sometimes, a simple, generic arrow pointing in a given direction more than suffices. And that's what Vision Quests are often about finding, for Chakotay.