it seems to me that is does not return the SOAP headers as it states in the explanation, but the request headers....
(PHP 5, PHP 7, PHP 8)
SoapClient::__getLastRequestHeaders — 直近の SOAP リクエストヘッダを返す
この関数にはパラメータはありません。
直近の SOAP リクエストヘッダ
例1 SoapClient::__getLastRequestHeaders() の例
<?php
$client = SoapClient("some.wsdl", array('trace' => 1));
$result = $client->SomeFunction();
echo "REQUEST HEADERS:\n" . $client->__getLastRequestHeaders() . "\n";
?>
it seems to me that is does not return the SOAP headers as it states in the explanation, but the request headers....