Detective Shadzter has been on the case. I’ve been hunting through Instagram and everyone who’s posted the pic is indeed crediting that jayanator06 guy. The pic appears to have been on Instagram for a couple of days now.
First, I found a larger version of the pic, complete with the photographer’s surroundings at the bottom: (First Pic)
Jayanator06 made this comment:
I think it’s marenen @blaze_nd_kinomi
Then I found this: (2nd Pic)
That’s also credited to jayanator06, but in the comments he doesn’t seem to have much to say.
Either this is all fake, or he’s got hold of some official Sonic Boom artwork and is making his own posters with it.