Good afternoon,
first thank you from heart and mind, mind and heart; for reading, thinking, reflecting, responding, and above all explaining a possible solution and/or documentation to address this doubt.
We would need a way to get inside a SOAP Web Service the SAML Assertion, and then, send it directly to the endpoint throught a SOAP Operation.
Currently we have researched and developed how to get the SAML Assertion with the following code: