PHP SOAP request to send multiple stdclass objects - php

Question

I am trying to send a PHP SOAP request that has multiple stdclass objects. I cannot figure out how to send so the xml is properly formatted. The xml structure should look like the following (from SOAPui).
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:ass="http://assignment.soap.assignshare"
xmlns:xsd="http://request.assignment.soap.assignshare/xsd"
xmlns:xsd1="http://datamodel.assignment.soap.assignshare/xsd">
<soapenv:Header/>
<soapenv:Body>
<ass:SetStaffOnDutyStatus>
<ass:SasPubSetStaffOnDutyStatus>
<xsd:Source>VendorC</xsd:Source>
<xsd:Dest>?</xsd:Dest>
<xsd:PubEventMsgTag>1</xsd:PubEventMsgTag>
<xsd:EventSetStaffOnDutyStatus>
<xsd:Timestamp>Thurs,03 Nov 2016,20:20:00 GMT</xsd:Timestamp>
<xsd:EventAction>Set</xsd:EventAction>
<xsd:Staff>
<xsd1:StaffID>10</xsd1:StaffID>
<xsd1:Last>Doe</xsd1:Last>
<xsd1:First>John</xsd1:First>
<xsd1:Middle>?</xsd1:Middle>
<xsd1:Role>?</xsd1:Role>
</xsd:Staff>
<xsd:Team>
<xsd1:TeamID>319</xsd1:TeamID>
<xsd1:TeamName>5 East</xsd1:TeamName>
</xsd:Team>
</xsd:EventSetStaffOnDutyStatus>
</ass:SasPubSetStaffOnDutyStatus>
</ass:SetStaffOnDutyStatus>
</soapenv:Body>
</soapenv:Envelope>
My PHP file is
<?php
$a = new StdClass();
$a->SasPubSetStaffOnDutyStatus = new StdClass();
$a->SasPubSetStaffOnDutyStatus->Source = 'Demo';
$a->SasPubSetStaffOnDutyStatus->Dest = 'http://192.168.50.3:26001/SAIWebService';
$a->SasPubSetStaffOnDutyStatus->PubEventMsgTag = 1;
$a->SasPubSetStaffOnDutyStatus->EventSetStaffOnDutyStatus = new StdClass($b);
$b = new StdClass();
$b->EventSetStaffOnDutyStatus = new StdClass();
$b->EventSetStaffOnDutyStatus->Timestamp = 'Thurs,03 Nov 2016,20:20:00 GMT';
$b->EventSetStaffOnDutyStatus->EventAction = 'Set';
$c = new StdClass();
$c->Staff = new StdClass();
$c->Staff->StaffID = 10;
$c->Staff->Last = 'Harry';
$c->Staff->First = 'Potter';
$c->Staff->Middle = '?';
$c->Staff->Role = '?';
$d = new StdClass();
$d->Team = new StdClass();
$d->Team->TeamID = 319;
$d->Team->TeamName = '5 East';
$d = (object)array_merge ((array)$b, (array)$c, (array)$d);
$e = (object)array_merge((array)$a, (array)$d);
$wsdl = "http://192.xxx.xx.x:26001/SAIWebservice?singlewsdl";
$client = new SoapClient($wsdl, array(
"trace"=>1,
"exceptions"=>0));
$values = $client->SetStaffOnDutyStatus($e);
echo "REQUEST HEADERS:\n" . $client->__getLastRequestHeaders() . "\n";
$xml = $values->SasPubRespSetStaffOnDutyStatus;
print "<pre>\n";
print_r($xml);
print "</pre>";
The output of the PHP file does not include the values of objects $b, $c & $d. Appreciate any guidance on what I'm doing wrong to merge the objects. Output is below.
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:ns1="http://request.assignment.soap.assignshare/xsd"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:ns2="http://assignment.soap.assignshare">
<SOAP-ENV:Body>
<ns2:SetStaffOnDutyStatus>
<ns2:SasPubSetStaffOnDutyStatus>
<ns1:Source>Demo</ns1:Source>
<ns1:Dest>http://192.168.50.3:26001/SAIWebService</ns1:Dest>
<ns1:PubEventMsgTag>1</ns1:PubEventMsgTag>
<ns1:EventSetStaffOnDutyStatus>
<ns1:Timestamp xsi:nil="true"/>
<ns1:EventAction xsi:nil="true"/>
<ns1:Staff xsi:nil="true"/>
<ns1:Team xsi:nil="true"/>
</ns1:EventSetStaffOnDutyStatus>
</ns2:SasPubSetStaffOnDutyStatus>
</ns2:SetStaffOnDutyStatus>
</SOAP-ENV:Body></SOAP-ENV:Envelope>