Hey, @StephenShuler ...
Thanks for sharing your screencast with us!
Something I will mention that I noticed is that the course you are trying to send invites from is unpublished. That being said, anyone that has a student role does not have permission or access to join that course when the course is unpublished, and you will have to publish the course first before they are able to accept their invites.
If this issue persists after the course is published, I recommend checking the 'People' tab of the course, and ensuring that the user you invited is on the enrollments list. If they haven't accepted the invitation, or if they did but it still says "Pending" next to their name, completely remove their enrollment from the course and re-invite them and see if that will work for you.
Hope this helps point you in the right direction, please feel free to reach out with anymore questions! We'd be happy to help!
- Noah