"They might not let you in the gates. And you'd have to find the gates, too, rather than getting lost underground and wandering until you're dead. Dwarves aren't the most welcoming of outsiders to their city. And... yes. They look very different from corpses. There's certainly a decay aspect to them, but you'll know one if you see it. And you'll want to get away from it as quickly as possible, if you've no means of definitively killing it."

Unless the Outsider is very much like so many people in Thedas who charge in recklessly.