Pass Storyline Variable from SCO to SCO via LMS

Sorry if this has been posted elsewhere, but I've done some searching and can't find it.  I'm also stumbling my way through SCORM, so I realize I may be holding some misconceptions about how everything works together.

I am looking to pass a Storyline variable from SCO to SCO using SCORM 1.2 in Moodle.   Specifically, we are building a course that teaches users about a topic, and they can learn this material as it is applied to 5 different situations.  Once they choose the situation they would like to learn about, we would like to hold that variable from SCO to SCO so they don't have to choose anew each time.

I have read the technique for passing custom variables in Storyline via a results page.  Looks like this is using an automated setValue command, and I have successfully tested this technique for passing a custom variable into Moodle.  It seems to me, however, that we need to use a GetValue command of some sort to retrieve that variable from the LMS when a SCO starts.

So perhaps the Execute JavaScript trigger could be used to both setValue and getValue of our custom variable.  If this is the correct approach, however, I'm not sure of the proper Javscript syntax for addressing the API and using the setValue and getValue commands.  I've looked through the various files created when Publishing storyline (html files, xml files, .js files, etc.) to reverse engineer how it is addressing the API object (searching for LMSInitialize, for instance) but I can't seem to find any of these API calls.

Any advice on overall approach to passing variables from SCO to SCO via the LMS with Storyline, or specifics about addressing the API object from the Execute Javascript trigger would be appreciated.

Thanks!