Custom Episode Intro does not play (Duke Hard)

Introduced by r7797-ad85f45f / svn7804.

Forum: https://forums.duke4.net/topic/11158-custom-intros-dont-work/

Autoload version for easier checking: https://www.mediafire.com/file/dprksuzqcs8yvge/DukeHard-1.2.1-autoload.zip