Bumping your topic doesn’t help.
Additionally you might not get an answer over the weekend as they are not “working days” and I believe Monday is labor day, so you are looking at Tuesday for an answer.
You could try opening a developer support ticket instead rather than on the third party developers forum.
The documentation here might be relevant:
Changes to other elements of your game’s presence on Twitch, including banner art or the name, must be submitted via a support request.