Submitting Quiz results when player is closed

Hello!

We run a competition among our teams using a Storyline 360 Final Assessment. We have a request I have not been able to figure out:

Quiz needs to be graded and activity marked as completed when player is closed - marking unanswered questions incorrect. The quiz is timed and we have been successful if they run out of time, but we don't want them to be able to close the course and resume again later.

Our LMS allows us to limit registering again, and can mark complete - but I haven't been able to determine a way to submit results when the player is closed early.

I've attempted a trigger to submit results on each slide, but that did not seem to work. Tested in SCORM 1.2 and SCORM 2004 3rd edition.

Any advice to accomplish this? Thanks in advance for any ideas shared.