Storyline and Moodle not interacting correctly?

Hi all

I'm working on a Storyline activity that needs to be presented in my organisation's Moodle instance. The activity is made up of three freeform drag-and-dr0p questions, totalling 5 points (2 points for the first drag-and-drop, 2 points for the second, 1 point for the third), which report to a single results slide. I've tested the activity and the correct result appears on the results slide. 

However, for some reason, when I upload it into Moodle as a SCORM package, Moodle automatically awards 5 points for completing the activity regardless of what the actual score in the Storyline activity is. I can't figure out where the problem is and it's driving me crazy!

My settings in Storyline: publish as a SCORM 1.2, tracking using quiz result, and it's definitely tracking on the correct quiz result slide. I've also checked that the result slide is tracking the result of all three drag-and-drop questions.

In Moodle: uploaded as a SCORM package, grade set to Highest Grade, maximum of 5. (I've also tried Sum Grade, maximum of 5).

Any advice/opinions on where the problem may be would be hugely appreciated!