Hey @Bart,
We unfortunately cannot field technical support questions here in our “Pre-Sales Forum”, but just to comment on what you in some sense, I’m curious about what you said here:
I have disabled the capability publish_tribe_events for contributors.
How, specifically, did you disable this capability?
Depending on your method, what you might find a lot of success with is just using a Role-editing plugin to try and restrict Events access. There are many such plugins out there, this one is just one example I found on a quick Google search:
• https://wordpress.org/plugins/user-role-editor/
Since we unfortunately cannot field technical support questions here in our “Pre-Sales Forum”, if you have further technical questions about The Events Calendar please post in our free forums here → https://wordpress.org/support/plugin/the-events-calendar
Sincerely,
George