See that is something I could see as possible and even more compelling. Like you said the Inquisitors underestimated the poor slave and paid for it, which is still a powerful statement about your character without being too spectacular. It also leaves room open for future plots involving your char and those inquisitors because I am sure they didn't leave the encounter happy. Maybe your char ran into them at the Seminary, maybe one was an Archon during your characters demon year and made it even more hellish for the guy. I think it opens up a lot of doors.

Also when you write consider how the world would view your character, unless he hides it well a lot of people will still see an Omestri, even a church rep, as lower than low, though they may not say it openly.