"Only teachers are allowed to access this content" when attempting to view spread sheet.
Posted by Respondus Support

If the instructor permissions are not specified correctly in D2L Brightspace, the following error can occur when attempting view a student submitted spread sheet.

Please ensure that all instructor roles have the ability to “see user enrollments”.  It's also important to check all other necessary instructor permissions, as specified in the LockDown Browser Administrator Guide for D2L Brightspace.