Answering my own question. When posing the right question in search found the following:
Ok, I was able to get Epic Games to show up under the Organizations list on my Github account page. What I was doing wrong was instead of using my github username, I was entering the full email address used to login to github. You need to enter only the github username (Display name) on the UE account page. Hope this helps.
Perhaps Epic should state this on the account page.