Solution : https://service.sap.com/sap/support/notes/1399658 (SAP Service marketplace login required)
Key words :
set work item status, process work item, work item logically, authorization object s_wf_wi, logically deleted, delete logically, transaction swia, authorization check, system checks, authorization mentioned
Related Notes :
1396805 | "Logically Delete" function active in workflow transactions |
1286336 | SWIA: New "Logically Delete" function for mass processing |