Solution : https://service.sap.com/sap/support/notes/1618080 (SAP Service marketplace login required)
Key words : 
terms access control 2010, prerequisites rejected roles, rejected role, access request, approver rejects, simulation button, cancel option, previous stage, reject role, approval reason
Related Notes : 
       
| 1607067 | Master Note for SAP Access Control 10.0 - Support Pack 6 |