Found on this video: https://www.youtube.com/watch?v=YVCXBc-h63o
I play through the entire thing here. Pretty much the only stuff leftover from the original game was the ending cutscene, but other than that, for a hoax it looks like a pretty legit prototype on how unfinished it looks/feels.
MDTravis currently has 532,121 views spread across 280 videos for Sonic the Hedgehog. His channel published over 2 days worth of content for the game, or 38.62% of the total watchable video for Sonic the Hedgehog on MDTravis's YouTube channel.