Good afternoon Scott and welcome back!
Thank you for reaching out to us.
We are sorry to hear about the events tab disappearing on you.
I would love to help you with this topic.
It sounds like for some reason the Events Calendar (free) is not active.
Both the Events Calendar and the Events Calendar Pro need to be activated for things to work properly.
If you are having issues getting it to activate, you could simply delete the Events Calendar plugin (manually or through the plugins page) and reinstall it from scratch (no events will be lost in the process).
Let me know how that goes.
Best regards,
Geoff B.