It is a small error, no need to worry.....but....

You have to get all 3 versions of the true  ending in order to unlock the epilogue, but due to how I scripted the persistent.data, the unlock will not activate until you land on any of the true endings again. If you land on a true ending, just make a save there so after you've gotten all 3, load up one of your true end saves and play it through to the end, that will trigger the needed if statement to announce the epilogue has been unlocked and get the persistent.data that will allow you to see it when you press the Epilogue on the main menu.

I'm not exactly sure how to fix it, but it's not a game breaking error... easy to workaround, so if you're wondering why you didn't get the epilogue after getting all 3 versions of the true ending, this is why. Simply get any true ending again and it'll unlock!

EDIT: It was actually a very simple fix haha. I'll implement it in my next planned update, as I intend to add an ending gallery soon and maybe an image room to show a fuller shot of the character sketches as well as Tasha's upcoming poster art for the game! So look forward to that in about a week or so! For now, just use the workaround for the epilogue.