Issues with edit button in overall summary in performance document

Summary:

Employees can only edit overall summary and not manager . So , in the performance template , we have configured overall summary section for Managers to "Not Allowed".

So as expected , Managers cannot edit overall summary for employees but still there is an edit button which is available which is causing confusions for managers .

I tried to use Expression Language such as #{pageFlowScope.pDocumentInfoMap['pPerformanceRoleCode']== "WORKER"}

#{pageFlowScope.pParamMap['pLoggedInPersonId'] == pageFlowScope.pParamMap['pWorkerPersonId']}

But unfortunately it is not working. The problem with the first expression language is that the button remains available against the overall summary section even if employee has submitted evaluation.