I found the 'jakey mii' post. Doctoring 100% confirmed.

Right here: https://miiverse.nintendo.net/posts/AYMHAAACAAAYUKlhicTZbg

Screenshot for anyone who can't see: http://tinypic.com/view.php?pic=9kmcrn&s=8#.VLRTO4rF85g

You're probably thinking "how did you find it?" Well, using information already established, I knew that the date of the Grump session where the Jon post in part 18 was censored was August 11th. I figured out which episode in the series started on that session (part 13) and checked over the next several episodes if any ended/began during the Miiverse crawl screen - giving Barry ample offscreen footage to lift from. Sure enough, in Part 14, they play the stage Big Bounce Byway, beat it and finished the episode/began the next with the Miiverse posts still scrolling.

So I go to the Miiverse SM3DW webpage, look for posts tagged to that level and scroll through FIVE MONTHS worth of it to go back to 8/11/14. While doing so, I realize that the Mushroom stamp is the one awarded during this level (confirmed by mariowiki.com) and it's the same one Jake used. Sure enough, it's there. Changed from "jakey mii" to just Jake, there's the post. Taken off of footage from between Grumps and doctored in over the JonTron post four episodes later.

You've been beaten, Barry.

This saga began with u/Sparxii finding inconsistency with SM3DW Part 18's Miiverse posts in [THIS THREAD] (http://www.reddit.com/r/ConspiracyGrumps/comments/2s4f9z/censored_miiverse_post_for_real/).

Here is the log of Big Bouncing Byway's Miiverse posts. (SM3DW Part 14/15)

Here is the log of Sprawling Savannah's Miiverse posts. (SM3DW Part 18)

TL;DR: In episode 18 of SM3DW a post about JonTron scrolls over the screen after the stage "Sprawling Savannah" and it is later doctored and replaced by a Miiverse post from the stage "Big Bouncing Byway" which had been played four episodes earlier.