It is important to know that the news will be shown in the players only when they are Approved. So when the RSS feed is configured so that the news is not automatically approved, the news will be downloaded with status Waiting for Approval and these will need to be approved to be shown on your players..
In order for you to approve a news item, your user group needs to have the permissions so that you can test. For more information on granting permissions, see information in Assigning Permissions to User Groups
To approve news, access to the list of news in the main menu News > News If you have questions about how to navigate through the options in this menu, see more information in How to View News
Locate the RSS feed that you want to approve or disapprove of the news and then click on the "Waiting" button:
You will see a screen with the preview of the news, with the options of Approve and Disapprove as shown in the previous animation.