Enable rule not showing in command checker and not run

Question

I want to remove the "Edit" button for selected records in a specific sub-grid in Project Contracts Main form.

I have customized the "Edit" button in Ribbon Workbench, and attached this Enable Rule to the command:

Enable Rule

Enable Rule 2

The JavaScript is the following:

ContractAgreementsFormCustomization = {

    forContractAgreementsView: function (selectedControl)
    {
        "use strict";
        debugger;
        var currentGridName = selectedControl._controlName;


        var agreementGrid = "ContractAgreements_Subgrid";
        if (currentGridName != agreementGrid)
        {
            return true;
        }
        else { return false; }
    }

I have customized the Edit button in the Subgrid-Ribbon, but tried also to customize the Edit Button in the Home Ribbon.

But this Script is not run and does not show up in the Command Checker for the Ribbon.

any ideas what could be the problem here?

thanks, Ulli