The Letter of the Day and Number of the Day mechanic is fantastic, I could see myself using them outside of this adventure.
Great choice to have a narrator for the booklet and I like the idea of using an episodic format for different adventures in the same location.
If I were to run this, I would probably change some of the names and try to be subtle about the source material. I think it would be a great 'a ha!' moment if players pieced it together on their own.