Postman request not working

My goal is to make a SOAP request to in PHP/curl. It is documented (https://peppol.helger.com/public/menuitem-validation-ws2) but I don't manage to make it work.
So I thought to make the request in Postman where I can export it to php/curl. But even there, I can not let it work.

On the contrary, in SOAPUI or in ReadyAPI I managed to make a good request with the expected return. That's working perfect, but both have no possibilty to export to php.

This is the request in Postman:
POST: http://peppol.helger.com/wsdvs?wsdl
Query Params: wsdl
Headers: content-type = text/xml + SOAPAction = validate
Body > Raw > XML: html-encoded XML wrapped in an envelope (I use the envelope that SOAPUI has autocreated, but it is different from the envelope on the publishers page)
The VESID parameter is added to the xml.

Whatever I try, the resulting xml is just the wsdl-file...

Another solution could be to export the SOAPUI-project and import it in Postman, but that seems not to work for wsdl.

I hereby add the result of the Postman Console in attachment. I hope anyone can help me to find out what I'm doing wrong.

I am not sure but maybe it has something to do with POSTAction 'validate' that must be defined elsewhere.
Thanks a lot!