the course once completed, it does not display the quiz

So to confirm:

• User takes a course and completes it
• Course is marked as complete in your LMS
• User now wants to open course again and review... the final quiz? the entire course? his/her answers?

Just not sure what is being asked here. I think you are asking if there is a way for the user to open (launch) the course again after it's marked as complete in the LMS and review the quiz or answers.

To my knowledge, the only way to accomplish that would be to have your LMS admins delete the completion record for the individual user, and then that would allow the user to take the course (and quiz) a second time.

If you are asking "how can a user review his/her answers to a quiz" once the user completes the quiz but before it's marked as complete in the LMS - the best way to do this would be to set up the "Results" slide as it comes pre-set in SL: one of the default options is a "Review" button. If the user selects "Review," then he or she can review the quiz or assessment that has just been attempted or passed. But if the course has been marked as complete, then that would not be possible since the module would be closed entirely.