If you switched the theme and the map starting working, then how is that the result of a plugin conflict?
In any case, you can safely rule out a plugin or theme conflict on a live site by installing the Health Check plugin. The Health Check plugin has a “Troubleshooting mode” that can be used to deactivate plugins for the admin only (everyone else will continue to see the site as normal with all plugins activated).
After you install the Health Check plugin, you go to WP → Dashboard → Heath Check → Troubleshooting. There you’ll Enable Troubleshooting Mode, then once that’s activated you’ll reactivate Event Espresso only via the Health Check’s Troubleshooting item in the WP admin bar. Then at that point you can reactivate plugins one by one until you find the map is broken again.