Hi Nimrod.
as per my understanding the SOAP header from receiver SOAP adapter will contain the same information as you can see in SOAP UI when you post a message to a assync WS. The main point of the ACK from SOAP connection is the HTTP status.
There are several HTTP status and the sucessfull one is 200. Then you can set alerts when the HTTP is not 200 that will trigger alerts with the message ID which you can give some support to them.
or/and you can implement BPMs (older version PI7.11) IN BPM you work with ACK in the send step and if the ACK is not sucessfull then it may go to the Exception node and you will know that the message was not posted sucessfully.
hope it helps?
Regards,
Diego