Why headless ? If non technical admin will post details about events, you can find a WordPress plugin for it and setup a WP site. Headless makes sense if you want to really customize the experience but you want "cheapest option" so I would assume they cannot pay for customizations anyway.
How else are they going to synergize with the latest paradigm shift?
Headless is for sharing a common backend between a web site and phone apps. If you don't have the resources for the apps then it serves little purpose.
