Vendor is asking about sending specfic information over in cxml

I have a question I am hoping that you can answer it for me.

In the session connection from Oracle to our Punchout, I notice that nothing is sent to specify which location is logging in. No addressID is provided in the cXML.

The vendor was looking to have the location come over when we first make the connection to the punchout so they can take the location and automatically connect them to the correct place on their side. The cXML they sent over is the connection code, not the information that gets pushed later, that is all fine, the location comes over then but isn't coming over when the user picks the punchout from the dropdown. thanks!