Why are my approvers missing the Approve buttons when viewing timesheets in their approval queue?
One possible explanation is that the time period is only open to Admins. If this is the case, then an Admin approver in the Unanet system will see all the buttons to approve the timesheet but the non-Admins will only be able to view the timesheet in their approval queue.
To see if the time period of X/XX/XX to X/XX/XX is only open to Admins, navigate to Admin > Setup > Time > Time Periods. If you want your non-Admins to approve the timesheets, you can edit the time period (by clicking the Edit Pencil Icon), deselect ADMIN ONLY ACCESS, and Save.