The scenario is that you have user A that submits a timesheet to workflow for approval. User B is will be assigned the workflow to approve it. The problem is that after user A submits the timesheet batch processing tries to process the Workflow batch and you get the message:
User B has no access rights to menu item TSWorkflowApproval.
We found that besides having access to the TSWorkflowApproval menu item, the user group that User B is a part of also needs view permissions to the project then daily key. For the daily key set everything else no access permissions except Timesheet approval, Timesheet Details, and Timesheets. These three options (Timesheet approval, Timesheet Details, and Timesheets) are granted full control permissions.
After setting these permissions for the user group that user B is a part of the batch job should process successfully.