It is not "ARI Stream Quiz" issue. This problem with WPFC or with settings. Our plugin generates dynamic content and sends/loads some data via AJAX. It uses
WordPress nonces for security reasons when send requests. Nonce has a lifespan and if lifespan for cached pages with quizzes is more than nonces lifespan then requests will be sent with old nonce and these requests will be ignored. Some cache plugins can handle nonce, but it seems WPFC doesn't support this ability so possible solution limits cache lifespan to 10 hours.
PS:
This article can be helpful.
Regards,
ARI Soft