RF_ReportingStructure control uses multiple rules to display the hierarchy. If you want to customize this, you might have to save all these final rules with different set of names and change the flow accordingly.
The anchor tags are appended in showEmpTree HTML rule. You can remove or update this.
Do you want to show this button in the operator id form itself ?
If yes then doing so many modificaiton might not help as you have to then change the operator id ruleform as well in order to call the newly created rules .
if your requirement is to show this option in somewhere else, then apart from what Sashi suggested, you can as well try to put the control inside a wrapper section and make the complete section as read only. This way it can probably help.