learndash_is_topic_complete()
Function: Checks if a topic is complete.
Source: includes/course/ld-course-progress.php:1325
show_quiz_continue_buttom_on_fail
Filter Hook: See snippet https://developers.learndash.com/hook/show_quiz_continue_buttom_on_fail/
Source: themes/legacy/templates/quiz/partials/show_quiz_result_box.php:287