Great news! Most of the time, it’s a setting issue.
Access your dashboard settings like on the screenshot below:
Click on "Select All" and "Continue"
Then make sure you select "Completion percentage does not influence my grading".
From here you should be able to see all the simulations that your students have taken.
For a complete view of your dashboard, you can read this article:
Please do not hesitate to reach out to our support team if you have any questions or are in need of assistance.