First of all, always make sure that your PPU Helper is running and is connected to the correct event, for which your desired share options are selected in Event Manager. Once you've confirmed that the Helper is running and the correct event is selected, and that the desired share options are selected in the event, check to make sure that the share screen is not disabled in PBU.
In PBU Settings>Preferences, check if the Disable Share Screen option is enabled. Uncheck this box to allow the Share screen to appear in PBU. If the share options still do not show up, make sure your desired sharing options are enabled in Event Manager.