Does Results Slide have to be visible to learner, in order to communicate results to LMS?

Well...not entirely true.

I have a Storyline test suite (modeled loosely after the AICC/CMI Test Suite Andrew Chemey built in Macromedia Authorware many years ago) which bookmarks sections as they are completed, changes the welcome page based on if this is the initial launch or a subsequent launch, and provides a rudimentary assessment (locked until all other sections have been completed).

It scores just like any other Storyline assessment would, however, the learner never sees the built-in Results slide, as it is safely tucked into an inaccessible scene. The "results" slide I use displays the built-in Results.PassPercent and Results.ScorePercent variables, however, it first sets numUserScore (a variable I created) to Results.ScorePercent. It also uses the built-in Results.ScorePoints variable to either display the Success layer or the Failure layer.

The SCORM communication to the LMS is handled entirely by JavaScript, some of which has been discussed previously on this forum. This includes the bookmarking, user preferences (like language, speed, and narration), score, and completion status. The Publish > Reporting and Tracking > Tracking is Using triggers (e.g., 'complete course'); the Results slide check box is unchecked and the the slide itself is disabled.