I'm in agreement with some of the previous commenters in that renting out a movie theater is pretty much the worst idea possible for a community event. The purpose should be to hang out with the community and have a few laughs, hopefully at Wombat's expense, and not to pay for someone's ticket...
Here is a link to a rather vague description from the EA FAQ on Syndicate: https://help.ea.com/article/syndicate-faq#coop
It's unfortunate that adding members to your Syndicate is not as easy as adding people to your friends list. You invite people to your syndicate by highlighting the user...
Just created a CAG group on Syndicate: CAG (CheapAreseGamer was necessary to work around the profanity filter). Send me a message or post here if you want an invite. Tip: Syndicate members get an experience bonus to more quickly unlock weapons and research.
Is anyone interested in starting a syndicate for CAGs? I'm a co-op addict and would love the experience bonus that comes with being a member of a group. I'll create the syndicate so just hit me up if you want to join.