I don't know what would be best. I mean, people will know that they are getting another audiobook, but eyebrows will be raised if the title is "Episode Shin-Ra".
On one hand, it is not a "bad" thing to have it named "Case of Shin-Ra". It tributes the way that English fans tend to name these chapters and it would keep things uniform. This also helps distinguish your audiobooks from for example our translations which bear "Episode" in their titles.
Keep in mind that these audiobooks are your achievements, so you should not feel the weight of having to be "painfully correct" about the naming.
On the other hand, if you can campaign and make known the title changes from "Case of" to "Episode" and possibly prepare people for the change (via, for example, facebook) then that could work as well.
Question: Is the Midgar reactor supposed to be mirrored that way? The symbols are all backwards.