1. Enable Backstage view mode

radRibbonBar1.ApplicationMenuStyle = Telerik.WinControls.UI.ApplicationMenuStyle.BackstageView;

2. Add BackstageButtonItem and BackstageTabItem to the Application Menu.

3. Run the program and run the accessibility tool "inspect.exe"

4. Select MSAA in "inspect.exe" and hover over a Backstage item.

As you can see in the attached screenshot BackstageButtonItems and BackstageTabItems are not accessible by inspect.exe.