Let's not confuse the issues with facts. The important thing is that The Marker was making Issac see the wrong person doing things, but it actually was a person doing things rather than these things happening on their own.
THQ's corps hasn't even been cut up and sold off and you're already making jokes about them? How tasteless!
Am I the only one who didn't realize Corvo was going to be betrayed until it actually happened? I honestly had no idea. It seemed really obvious on my second play though.