In this episode, we get down and dirty in the cleanest, most pristine sewers on Earth.
It feels weird to criticize this game for anything involving its story content. I say that mostly because it clearly wasn't a major focus of the game. It's not accident that the cutscenes are all less than 5 minutes. Like I said in the episode, it's a well-documented fact that Rhianna Pratchett was hired after all the levels in the game were made.
There's also the fact that this game was made in the late 2000s, back when storytelling in games was just starting to be a thing that people began taking seriously. It was probably assumed that Mirror's Edge didn't need much of a story, so long as the game played well enough.
In that way, I can't blame it for being a product of its time. While indeed unique among its contemporaries, even today, it still has signs of being developed in the era where "Call of Duty" was a phrase that wasn't nearly as divisive.
That said, I would have loved it if the game did a bit more to tell players about the world and the people in it.