Howdy macsol & firestep,
Thank you for running through those trouble shooting steps. Now that we have isolated it we can skip right to figuring out a solution.
First thing I would do if I was you is update the theme if possible. If not, contact the theme developer. They have evidently created some customizations for the site when run in tandem with The Events Calendar. I bet the author has simply not had a chance to release an updated version of the theme that works with TEC 3.7. While you wait for it to be fixed, you might try simply renaming this folder ../wp-content/themes/advocator/tribe-events/ from “tribe-events” to “tribe-events-bak”. That should remove any customizations the theme author has done. But it might also adversely affect the sites look, in which case you would want to rename it back.
Does that work for you and fully answer your question? Please let me know. Cheers!
– Brook