Check the comments of the rating page.
Also, it shows it was published 19 days ago, so if he had made it, it wouldn't fit the rules of the jam.
Either way, that is still plagiarism, since a) you didn't credit Hobson-TV anywhere (your project wasn't even a remix!) and b) it is still his game which was created over a YEAR BEFORE THE JAM!
It's not even the entry xD
That doesn't matter, you still stole someone else's work and claimed it was your own. That's plagiarism, and that's wrong to do.
Remember: Scratch automatically gives credit on remixes. Seriously, guys?
it was an entry, until you took it off