Hey Steve,
Thank you for reaching out to us!
In general, Events follow the same user roles and permissions as any other default post in WordPress. Please check the following article: it has useful information about roles and permissions:
Editing User Roles and Permissions
With the Members plugin, you should be able to tweak the default user roles and achieve what you want.
I hope this helps! If you have any other questions at all please feel free to let me know and I’d be happy to help as best I can!
Cheers,
Patricia