The purpose of a game jam is that you make a game during the jam. In this case it's pretty obvious that you made most (if not all) of it before the jam even started.
If you are looking to promote your current project, then how about creating a stand-alone spinoff of it for this jam? If you don't want to invest all that effort on just a game jam submission, then remember that you can still use any of the assets created for your jam game in your main project later.