I also have that same issue. The combination of MetaSlider and The Events Calendar Pro does cause an issue when either trying to edit an already published recurring event or trying to publish a saved to draft recurring event.
After turning off MetaSlider I was able to see the lightbox that asked me if I was going to update the current event or all recurring events.
Is there any updates to this? I would be happy to send any troubleshooting files necessary to help fix the bug.