Resolved.
If anyone else needs the answer, you can change the following line in your Moodle's mod\scorm\report\basic\classes\report.php from:
$attemptsmode = optional_param('attemptsmode', SCORM_REPORT_ATTEMPTS_ALL_STUDENTS, PARAM_INT);
to
$attemptsmode = optional_param('attemptsmode', SCORM_REPORT_ATTEMPTS_STUDENTS_WITH, PARAM_INT);