This was originally a fork of Jackathan/MarcLaidlaw-Epistle3, but I think there have been made enough changes that this stands out as it's own repository. Thanks to @Jackathan! I'm trying to maintain the whole thing and merge the original pull requests and stuff here. If the blog post or the tweets get deleted somehow, you can still read all the content here or at https://github.com/Jackathan/MarcLaidlaw-Epistle3 if this repo is too bloated for your taste.
So far this repository includes many of the original pull request, many additional translations, some minor improvements and the Epistolary Afterthoughts by Marc Laidlaw.
Here you can view the original version, as well as the corrected version which has all the obfuscated names switched back to the real names.
Here is a list of all the names that have been changed to their "original" equivalent:
"Playa" : "Player"
"Gertie Fremont" : "Gordon Freeman"
"Gertrude Fremont" : "Gordon Freeman"
"Hyperborea" : "Borealis"
"Mrs. X" : "G-Man"
"Disparate" : "Combine"
"Jerry Maas" : "Judith Mossman"
"Alex Vaunt" : "Alyx Vance"
"Ghastlyhaunts" : "Vortigaunts"
"Elly Vaunt" : "Eli Vance"
"Tocsin Island" : "Aperture Science"
"Wanda Bree" : "Wallace Breen"
The original source is Marc Laidlaw's website, at https://www.marclaidlaw.com/epistle-3/.
If you want a little more info, watch this video by ValveNewsNetwork: https://www.youtube.com/watch?v=urza2sbU68Q
Here is another video by ValveNewsNetwork regarding the HL3 map leak and some Episode 3 speculation: https://www.youtube.com/watch?v=h3m7Oc08Ur0.
A bunch of awesome people also including @Jackathan set up a mod called Half-Life 2: Aftermath where all the leaked items and maps are packaged up and ready to play: https://www.moddb.com/mods/hl2aftermath
Here are some further archives of Marc Laidlaw's original post:
https://web.archive.org/web/20170825025137/marclaidlaw.com/epistle-3/