To put it simply, there's multiple timelines and versions of Chris's life. There are a couple constants in each timeline, of course. His personality remains the same throughout, and not a single iteration of him is aware of the other timelines. (Though that could change, I've been tossing it around.) Even Chris coming to PAM could be a timeline separate from other ones. From a writing perspective, this not only allows me to put him in as many roleplay/writing scenarios as I want, but allows me to experiment with ideas that I normally wouldn't accept into the canon story.