How can I create a graded multiple choice question with a video?

Hi! I am working on a course for a client and have created separate videos for each question and answer. For example, question 1 is a video that reads the question and each answer choice. I have created "invisible" buttons that span each choice and set the button for the correct answer to skip to a correct video, while any other choice takes you to an incorrect video that reads out the correct answer. Each question video is in a mc slide, so I can fill out the form view, however, because I do not want the text to show up (just the video), it isn't picking up correct/incorrect responses in SL in order to grade them. I do not want to have to remake these questions in SL. I would rather use the videos, however, the client does want some sort of grade for each person at the end of the quiz. Any suggestions?