conflict for sign ups

I use a CMS platform called LearnDash so my users can take courses. To use learndash the customers create an account on WordPress then take the course. However, I also want the customer to sign up here AFTER they take the course: https://www.freelancermasterclass.com/registration (This is a Users Ultra form). The users are getting a “your already registered” error because they already registered for one of the courses. However, the problem here is only want to give access to the form /registration AFTER they completed the coursework. Is this possible?