I'm trying to hide a whole subtab for a specific user. The subtab can't be hidden using the NetSuite UI, so I am hiding it via SuiteScript:

/**
 * @NApiVersion 2.x
 * @NScriptType UserEventScript
 * @NModuleScope SameAccount
 */
define(['N/record', 'N/ui', 'N/ui/serverWidget'],
/**
 * @param {record} record
 * @param {ui} ui
 * @param {serverWidget} serverWidget
 */
function(record, ui, serverWidget) {
	return {
		beforeLoad: function (context){
            var sublist = context.form.getSublist({id: 'item'});
            sublist.displayType = serverWidget.SublistDisplayType.HIDDEN;
            var currencyField = context.form.getField({id: 'currency'});
            var exchangeField = context.form.getField({id: 'exchangerate'});
            currencyField.displayType = serverWidget.FieldDisplayType.HIDDEN;
            exchangeField.displayType = serverWidget.FieldDisplayType.HIDDEN;
        }
	};
});

I am able to hide the sublist ('item') pretty easily, but am having trouble on the fields.