Looks like I need to get the All-in-One Events Calendar and Events Manager to work on the same Calendar. I need one Calendar that has all the events listed on it using the All-In-One plugin. If one of the events on the Calendar is my event, that's where Event Manager should come in. So people can click on the event and RSVP for the event, buy tickets, etc. if an event is another organization's event, the visitor needs to be able to click on it and RSVP with that organization's web link that handles that.