I spent so long working on this and it just doesnt open when you try to play it :(
This was my first Jam and I ran into a couple issues that had me panicked. The solutions I finally came across may help you out in the future.
After uploading, you need to run the game once before you can 'publish' it. Only after publishing can your game be linked as your Jam submission
First Issue - for me, when trying to run the game the first time, I was stuck on 'Loading game for the first time...' for hours. In my case, it was because my browser had shields up and was blocking scripts/java...whatever was needed. It worked immediately after changing my browser.
Second Issue - now the game would actually try to load, I still got a 'Unable to parse build' warning preventing the game from actually loading. This turned out to be a compression issue when generating the build (in Unity). I needed to change the WebGL build setting to change (or disable) the type of compression being used. This can be found in the 'Publishing Setting' and is called 'Compression Format'
Not sure if this will help you. Very sorry to hear about your submission after all the hard work.
I actually have a very similar problem. There's a bug in my game which crushes scenes' transitions and doesn't allow you to move to the other scene after the first mini game. We've aleready fixed the problem in a new build but as we can't upload it to the site till the end of the voting, no one can actually play it. That's sad cosidering the fact how much effort the development process took