This would be my first time submitting anything to a game jam, but from what someone else said, it looks like you upload a game to Itch and then somehow link / submit that game to the jam? In which case, the upload is linked to your Itch account and you probably just have to credit the people involved rather than systematically binding multiple social profiles as "co-owners" of the submitted work.
Again, this is my first time, so take with a many grains of salt.