Cannot customize event-editor.php

Hello,
I am trying to customize event-editor.php by adding it to my child theme OR to the plugin-templates directory. Nothing is working, none of my edits there show.

I have tried adding the file to:
/wp-content/themes/my-child-theme/plugins/events-manager/templates/
/wp-content/themes/my-child-theme/plugins/events-manager/templates/forms/
/wp-content/plugin-templates/events-manager/templates/

Could you please advise me where I am going wrong here?
Thanks