Branched quizzing with a single result

Hi,

I'm not sure if this has been addressed elsewhere and the search feature just isn't working in here today, so here goes...

I have a course that will be taken by four different groups. At the start of the course they will select one of four branches depending on their group. At the end of each branch is a quiz specific to their group.

My question is, if each learner will take only one of the four quizzes and won't even see the other three, how can I report their result to an LMS with a proper percentage? If I create a result slide that draws on all four result slides for the four quizzes, the maximum any learner can score will be 25%. How can I report a score out of 100% when all of my learners will have taken only one out of the four possible quizzes?

Thanks!