Is it possible to have additional Chat tabs that can be associated to a particular white list email address
You can’t do that with the built in chat tab as it’s global to the whole app. You can however add a chat component inside each part of your app that is only visible to that particular list of people. If a user cannot get to a particular record, then the chat component for that record is not available to them. Chat components can be linked to a particular record in a list (sheet).