PI 7.5 REST Receiver XPath Expression Removing Tags

Hello,

I am trying to use a REST Receiver in PI 7.5 (Single Stack) to call a web service. The end point is generated based on an XML message that is created with message mapping. The document is formatted below (DispatchRequest).

In the communication channel, I am trying to use an XPath Expression to append the entire XML document to the end of a static URL. I am currently using the expression "/descendant-or-self::node()" but that results in the XML document without any tags. I would like to pass the document with the tags and values. I have tried multiple different XPath expressions with no luck... are there any possible ideas on how to pass the XML as-is at the end of the URL?

Here is the configuration currently:

Thank you for your help!

<?xml version="1.0" encoding="utf-8"?>
<DispatchRequest>
  <vendorCode>RDWY</vendorCode>
  <accountConfig>
    <siteLoginName>LOGINNAME</siteLoginName>
    <credentials>PASSWORD</credentials>
    <direction>O</direction>
  </accountConfig>
  <accountNumber/>
  <referenceNumber>123456789</referenceNumber>
  <bolNumber>123456789</bolNumber>
  <scac>RDWY</scac>
  <quoteNumber>987654321</quoteNumber>
  <createBOL>FALSE</createBOL>
  <origin>
    <address1>123 MAIN ST</address1>
    <companyName>TEST COMPANY</companyName>
    <city>ANYTOWN</city>
    <stateName>TX</stateName>
    <country>US</country>
    <postalCode>12345</postalCode>
    <phoneNumber>800-555-1212</phoneNumber>
  </origin>
  <destination>
    <address1>123 MAIN ST</address1>
    <companyName>TEST DESTINATION</companyName>
    <contactName>TEST DESTINATION</contactName>
    <city>ANYTOWN</city>
    <stateName>TX</stateName>
    <postalCode>12345</postalCode>
    <phoneNumber>800-555-5555</phoneNumber>
  </destination>
  <lineItems>
    <item>
      <code>PRD</code>
      <quantity>33</quantity>
      <weight>740</weight>
      <weightUnit>lbs</weightUnit>
      <freightClass>100.0</freightClass>
      <description>MARKERBOARD</description>
      <hazmat>false</hazmat>
      <pieces>122</pieces>
      <stackable>FALSE</stackable>
    </item>
    <item>
      <code>PRD</code>
      <quantity>3</quantity>
      <weight>118</weight>
      <weightUnit>lbs</weightUnit>
      <freightClass>65.0</freightClass>
      <description>GLASS-CLEAR</description>
      <hazmat>false</hazmat>
      <pieces>5</pieces>
      <stackable>FALSE</stackable>
    </item>
  </lineItems>
  <dockCloseTime>23:59</dockCloseTime>
  <billTo>
    <address1>321 Primary Rd</address1>
    <companyName>BILL TO COMPANY</companyName>
    <city>NEW YORK</city>
    <stateName>NY</stateName>
    <country>US</country>
    <postalCode>10001</postalCode>
    <phoneNumber>800-555-1212</phoneNumber>
  </billTo>
  <pickupDateTime>2016-12-05T14:59:00Z</pickupDateTime>
  <deliveryDateTime>2016-12-08T21:29:00Z</deliveryDateTime>
  <pickupPhone>616-555-5555</pickupPhone>
  <pickupContactCompany>PickUp Company Name</pickupContactCompany>
  <deliveryContactPhone>800-555-5555</deliveryContactPhone>
  <emailBOLShip>false</emailBOLShip>
  <emailNotifyShip>false</emailNotifyShip>
  <emailApptShip>false</emailApptShip>
  <emailDelivShip>false</emailDelivShip>
  <emailBOLCons>false</emailBOLCons>
  <emailNotifyCons>false</emailNotifyCons>
  <emailApptCons>false</emailApptCons>
  <emailDelivCons>false</emailDelivCons>
  <emailConfirm>false</emailConfirm>
  <pickupStartTime>21:30</pickupStartTime>
  <pickupEndTime>21:30</pickupEndTime>
  <deliveryStartTime>2016-12-08T21:29</deliveryStartTime>
  <deliveryEndTime>2016-12-08T21:29</deliveryEndTime>
</DispatchRequest>