Yeah, I suppose it could have just been a quick way to quietly subdue the guards. Perhaps there was no intent there to hint at the Dark Side for Luke. It’s just a moment that made me raise an eyebrow a bit.
It’s weird to have Mind Tricks as a Dark Side power, though. I figured the Dark Side equivalent of it would be something like the Imperius curse from Harry Potter: invading someone’s mind and taking away their free will completely.