Stuck at converting xml request to corresponding Savon request - php

Question

I am trying to communicate with a 3-rd party API. I tried both savon and Soap UI but both failed, then I asked them and they gave me equivalent that works. Confused, I toggled the logger and got following XML request which is quite different from what Savon is sending.
Here is the PHP code (I guess that's not needed, but still)
$apiauth =array('UserName'=>'XXXXXX','Password'=>'XXXXXXX','ClientCode'=>'1234')
$wsdl = 'http://stagewebapi.mylescars.com/service.asmx?wsdl';
$soap = new SoapClient($wsdl);
$header = new SoapHeader('http://tempuri.org/', 'AuthHeader', $apiauth);
$soap->__setSoapHeaders($header);
$data = $soap->fetchCities($header);
print_r($data);
Here is the XML request that PHP is sending and which is working just fine
<?xml version="1.0" encoding="UTF-8"?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ns1="http://tempuri.org/"><SOAP-ENV:Header><ns1:AuthHeader><ns1:UserName>XXXXXXX</ns1:UserName><ns1:Password>XXXXXXX</ns1:Password><ns1:ClientCode>1234</ns1:ClientCode></ns1:AuthHeader></SOAP-ENV:Header><SOAP-ENV:Body><ns1:fetchCities/></SOAP-ENV:Body></SOAP-ENV:Envelope>
Here is my ruby code so far
require 'savon'
auth_header = { 'UserName'=>'XXXXXXX','Password'=>'XXXXXXXX','ClientCode'=>'1234'}
client = Savon.client(:wsdl => "http://stagewebapi.mylescars.com/service.asmx?wsdl",
:namespace_identifier => :ns1 ,:namespace => "http://tempuri.org/" , :log => true, :soap_header => auth_header,
:pretty_print_xml => true, :env_namespace => 'SOAP-ENV')
puts client.call(:fetch_cities)
Here is what Savon is producing
<?xml version="1.0" encoding="UTF-8"?>
<soap-env:Envelope xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ns1="http://tempuri.org/" xmlns:soap-env="http://schemas.xmlsoap.org/soap/envelope/">
<soap-env:Header>
<UserName>XXXXXXXXXXXXXXX</UserName>
<Password>XXXXXXXXXXXXX</Password>
<ClientCode>2873</ClientCode>
</soap-env:Header>
<soap-env:Body>
<ns1:fetchCities/>
</soap-env:Body>
</soap-env:Envelope>
I don't know how to make it equivalent to the PHP one. Am I missing something obvious ?
I tried to look at Savon documentation to find if there are some methods to manipulate tags with fine grain control but couldn't find much about it.
Questions similar to this are either unanswered or are specific to the requests.
Some SO questions that helped a little
Convert this xml request to a proper savon request
Replicating xml requests with savon ruby
Little curious, how PHP gets it right most of the time. Is it the parser they use for wsdl?