We have a game on Google play created with a developer account and then we have admin access to that game trough our personal accounts (we are multiple developers). Recently
Ok, after talking with Google support, it seems there is a page to control which accounts has access to which games, it is https://console.developers.google.com, and from there you can configure permissions without problems and it works (tested it). You have to sign in as the account owner to have full access to all games.