Hey, thanks for sharing all those details and welcome (or welcome back!) to the Streamlit community! 
You’ve done a fantastic job troubleshooting—revoking OAuth, re-authorizing, and confirming org access are exactly the right steps.
Unfortunately, when you rename a GitHub organization, Streamlit Community Cloud may still reference the old org name due to how it caches GitHub coordinates (owner, repo, etc.). This is a known limitation: Streamlit identifies apps and workspaces by the original GitHub coordinates, and renaming an org doesn’t automatically update Streamlit’s backend. The only way to resolve this is for the Streamlit support team to update their database manually or for you to delete and redeploy any affected apps under the new org name. If you need to keep the same app URL, you must delete the old app (freeing the subdomain) and redeploy from the new org. For more, see the official docs and related forum threads: Rename or change your app’s GitHub coordinates, FAQ: Read-only access after changing GitHub repo/org name, and Forum: Server error after org rename.
If you’d like, you can open a support ticket or reply here with your details (which you’ve already provided—thanks!) so a Streamlit admin can update the backend for you. In the meantime, deleting and redeploying is the fastest self-service workaround. Community members, feel free to jump in if you’ve found other solutions!
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