I actually may have - as long as you create the page (even unpublished), you have technically submitted to the jam, even if you don't upload any files. You can then upload files at your leisure, which doesn't seem to be restricted in any way by the dates of the jam. This makes sense, since once you siubmit a game to a jam you can update it post-jam, change things on the page, upload, etc. The loophole seems to be that a page without an upload counts as a "submission."
Anyway, thanks for hosting, and don't get discouraged - this is a great theme for a jam, and hopefully next time you'll get a bigger response!