What works with the new Apps Script runtime powered by Chrome V8 for this project?

Post edited to clarify:

I found the following code that allows me to query my 3dCart store database and dump the information into a sheet. I tried upgrading to the new Apps Script runtime powered by Chrome V8 and it fails. I get the following error:

ReferenceError: Xml is not defined (line 12, file "Utilities")

var api_key = "";
var store_url = "";
// These settings can be hardcoded or placed in the "SETTINGS" sheet

function queryCart(strSql) {
  // This script relies on the SoapService which was deprecated beginning 7/2013 and will be unavailable 2/2014!

  loadSettingsFromSheet();
  var wsdl = SoapService.wsdl("http://api.3dcart.com/cart_advanced.asmx?WSDL");
  var cartAPI = wsdl.getService("cartAPIAdvanced");

  var param = Xml.element("runQuery", [
                Xml.attribute("xmlns", "http://3dcart.com/"),
                Xml.element("storeUrl", [store_url]),
                Xml.element("userKey", [api_key]),
                Xml.element("callBackURL", [""]),
                Xml.element("sqlStatement", [strSql])
              ]);


//  var envelope = cartAPI.getSoapEnvelope("runQuery", param); // Use to examine request without sending

  var result_full = cartAPI.invokeOperation("runQuery", [param]);
  var result = result_full.Envelope.Body.runQueryResponse.runQueryResult;

  return result;
}