Once you have invited users to ReelDx, you can check if they have accepted their invitation. To read more about inviting users, go here.
First, go to the members tab on your institutional account.
Once in your members tab, you will see a list of invited users at the bottom of the screen. To check whether or not an invitation has been selected, simply look at the name of the user you have invited.
If the name reads "Unknown" under the First Name column, and "Unknown" under the Last Name column, that user has not accepted their invitation.
If these values have been filled in with the user names, then the user has accepted their invitation.