Response object:
{
  "Integrator": "ARVY",
  "MessageType": "AgentStoredProcMessage",
  "MessageTagId": "ARVY-000000108",
  "QueryResults": "<row PriKey=\"3\" Name=\"2/3 PROV\"/><row PriKey=\"1\" Name=\"Auto\"/><row PriKey=\"13\" Name=\"DIST\"/><row PriKey=\"6\" Name=\"ELECT\"/><row PriKey=\"2\" Name=\"HHG\"/><row PriKey=\"14\" Name=\"HHG Atlas\"/><row PriKey=\"8\" Name=\"HVP\"/><row PriKey=\"7\" Name=\"NONE\"/><row PriKey=\"4\" Name=\"O&amp;I\"/><row PriKey=\"12\" Name=\"RS\"/><row PriKey=\"5\" Name=\"TS\"/>",
  "OutParams": "{\"Parameters\":null,\"ReturnValue\":0}",
  "Results": true,
  "StatusCode": 200,
  "ExceptionMessage": null,
  "BaseExceptionMessage": null,
  "ResponseMessageCount": 0,
  "ResponseMessages": [],
  "ProcessingDate": "2023-10-04 19:44:46Z"
}

To read the Query Results as valid XML, add a <root> and </root> elements around the QueryResults, which would yield xml that looks like (after removing the escape characters and adding some readability formatting):

<root>
   <row PriKey="3" Name="2/3 PROV"/>
   <row PriKey="1" Name="Auto"/>
   <row PriKey="13" Name="DIST"/>
   <row PriKey="6" Name="ELECT"/>
   <row PriKey="2" Name="HHG"/>
   <row PriKey="14" Name="HHG Atlas"/>
   <row PriKey="8" Name="HVP"/>
   <row PriKey="7" Name="NONE"/>
   <row PriKey="4" Name="O&amp;I"/>		// <-- Notice the escaped ampersand (xml requires it to be escaped)
   <row PriKey="12" Name="RS"/>
   <row PriKey="5" Name="TS"/>
</root>

The above example came from this SQL:

select PriKey, Name = Commodity from CommType

PriKey      Name
----------- --------------------------
3           2/3 PROV
1           Auto
13          DIST
6           ELECT
2           HHG
14          HHG Atlas
8           HVP
7           NONE
4           O&I				// <-- Notice the ampersand
12          RS
5           TS

(11 rows affected)


// Sample C# snipet of how to process the returned XML string as a C# XDocument object:
var theXmlString = "<row PriKey=\"3\" Name=\"2/3 PROV\"/><row PriKey=\"1\" Name=\"Auto\"/><row PriKey=\"13\" Name=\"DIST\"/><row PriKey=\"6\" Name=\"ELECT\"/><row PriKey=\"2\" Name=\"HHG\"/><row PriKey=\"14\" Name=\"HHG Atlas\"/><row PriKey=\"8\" Name=\"HVP\"/><row PriKey=\"7\" Name=\"NONE\"/><row PriKey=\"4\" Name=\"O&amp;I\"/><row PriKey=\"12\" Name=\"RS\"/><row PriKey=\"5\" Name=\"TS\"/>";
var theXDoc = XDocument.Parse( $"<root>{theXmlString}</root>" );
var theRowCounter = 1;
foreach ( var theElement in theXDoc.Elements("root").Elements("row" ) )
{
	var theData = $"Row {theRowCounter}: PriKey={theElement.Attribute("PriKey").Value}, Name={theElement.Attribute("Name").Value}";
	theData.Dump();
	theRowCounter++;
}

// Produces this output (assume the Dump() method spits out the string's content):
Row 1: PriKey=3, Name=2/3 PROV
Row 2: PriKey=1, Name=Auto
Row 3: PriKey=13, Name=DIST
Row 4: PriKey=6, Name=ELECT
Row 5: PriKey=2, Name=HHG
Row 6: PriKey=14, Name=HHG Atlas
Row 7: PriKey=8, Name=HVP
Row 8: PriKey=7, Name=NONE
Row 9: PriKey=4, Name=O&I		// <-- Notice how the XML escaped ampersand was automatically handled correctly.
Row 10: PriKey=12, Name=RS
Row 11: PriKey=5, Name=TS