I don't know. Do you really think that it is THAT innovative that you can't redo it in a week? And there's no one controlling or checking if you wrote it during the jam time or before. Participating in a jam does not mean that you must be able to call everything from older objects directly into your head, there are also people looking onto Tutorials for their jam game.
I think that it makes no real difference whether you just put it in directly or write it new while constantly looking at how you have done it.
So, just use it.