Workflow monitoring for different roles

[mig1]

Hi all,
what is the best way to enable all parties involved into a workflow to see what the status of these workflows / process instances is?
For the initiator I can use the ProcessInstanceQuery by involvedUser, but for others I am only aware of TaskQuery by taskCandidateGroup, but it only delivers active tasks. Why are the users, who completed tasks in a process instance, not "involved"?

[mig1]

Sorry, the question was not specific enough - for the active process instances it works, but not for history. There is only a query for "startedBy" but nothing like "involved". Does anyone have experience on what has to be done other than maybe putting every user into a variable and retrieve by this variable later from history?
Thanks

[frederikherema1]

For 5.13, the identity-links have been added to the history as well (see ACT-1688 and https://github.com/Activiti/Activiti/commit/9c36f7a7f377fbaa5270cff530dfcf84b7fd64be), so this can be leveraged for NEW processes/tasks. For existing completed processes, I'm affraid this has been lost forever…