List vCD OrgVDCs

I thought this code in a simple workflow (passing a valid vcdHost) would list all the OrgVDCs in my vCloud Director that I can see in the plugin tree.

var queryService = vcdHost.toAdminObject().getAdminQueryService();

var expression = new VclExpression(VclQueryOrgVdcField.NAME, "*", VclExpressionType.EQUALS);
var filter = new VclFilter(expression);
var params = new VclQueryParams();
params.setFilter(filter);

var resultSet = queryService.queryOrgVdcRecords(params);

while (resultSet != null) {
    var records = resultSet.getRecords();
    System.log(records.length + " records found");
    for (i=0; i < records.length; i++) {
      System.log(records[i].name);
      System.log(records[i].id);
    }
    resultSet = resultSet.getNextPage();
}

However, it does not, telling me instead that there are "0 records found".  I know for certain there are two OrgVDCs visible both via the plugin and via the vCloud Director WebUI. 

Any pointers/guidance as to what I am missing?