Quiz reporting decision at run time

Hi. I'm using Storyline 1 update 8.

My learner selects a short or long version of my course which sets a variable that I use to determine which slides he sees. At quiz time, I send him to a short quiz or a longer quiz based on the variable. Both versions of the quiz draw from the same question bank but the short one eliminates a few questions.

My problem is that I'd like to use my variable to decide  which results slide to report to the LMS at run time rather than at publish time. Alternatively I could make a single quiz & results slide but would adjust which questions get used at run time based on the variable.

I've also tried a standalone results slide (that reports to LMS) that both quizzes go to, and but can't seem to set the built-in "Results...  variables.

Is there any way to accomplish any of these solutions? Is there something else I've missed that will accomplish what I'm trying to do?

Hope this made sense. Thanks for any help you can give.

ma