Update: from version 4.5.8 you can handle this easier: see here

Only quizzes that are published will be shown in “My Quizzes” page and the tabs from the Reporting module – for example the History tab.

What means a published quiz? This is a quiz whose shortcode is placed inside the content of a post, page, or custom post type. If you place the shortcode in some widget, custom field, via do_shortcode() call in your theme, or some other odd way, the system will not recognize the quiz as published and it will not be shown in these pages.

A very easy way to know if a quiz is published or not is by looking at your Quizzes page in admin (the first page when you click on WatuPRO menu). If the quiz title is not clickable, this means it’s not recognized as published.