Have you done one of these GDG Jams before? If it's a group they might have a contact person but I have zero clue about how any of that might work.
NGL if the theme doesn't come up I'll be doing the same and submitting whatever comes up.
There was a fan comic that got sent to blizzard YEARS ago in something like 2012 that explicitly went through the list of items that blizzard forbade comics from having, and made them into a satirical mishmash. Kinda want to do that here.
Regardless good luck man I look forward to playing your game!