Well, your submit data connection is still set to use the mapping.xml, just the mapping won't have any data to submit (that's the bit the qRules code does). So the data connection will submit the blank CAML Batch info to the list specified in the mapping.
Another way to check whether data connections that use SharePoint Web Services work in your environment is to create a query data connection to the CheckOutFile method - this one is pretty simple to use. For the parameters, set pageUrl to the URL of a SharePoint library item. Set checkoutToLocal to false and leave lastmodified blank. Make sure your query connection works in your test form in preview or client and then test as a browser form. Again, if the issue is the data connection, we'd anticipate that IPFS will give you an error when you try to execute the data connection.