this is the method description  it seems that you should your call parameters differently

method ExecuteProcedure(ByRef pResultSnapshots As %ListOfObjects,
        Output pOutputParms As %ListOfDataTypes,
        pQueryStatement As %String,
        pIO As %String,
        pInputParms...)
 as %Status [ Language = objectscript ]

The pOutputParms list returns the output values of all scalar output and input/output parameters.
This would result in this order

SET tSC = ..Adapter.ExecuteProcedure( , .outparmSQLQuery2 , "io*"pRequest.StringValue )

>> 1st par  - skipped
>> 2nd par = output byRef
>> 3rd par = SqlQuery
>> 4th par = io
>>par 5 ... query input parameters
 

This explains the log

as official documentation tells you:
https://docs.intersystems.com/iris20211/csp/docbook/DocBook.UI.Page.cls?KEY=GSQL_langelements#GSQL_langelements_ops_precedence

 
USER>SET status=$SYSTEM.SQL.Util.SetOption("ANSIPrecedence",1,.oldval)
 
USER>do $system.SQL.Shell()
SQL Command Line Shell
---------------------------------------------------

[SQL]USER>>SELECT 1+2*3+4*5
1.      SELECT 1+2*3+4*5
Expression_1
27
^^^^-----------------------------------------------
[SQL]USER>>q
 
USER>SET status=$SYSTEM.SQL.Util.SetOption("ANSIPrecedence",0,.oldval)
 
USER>do $system.SQL.Shell()
SQL Command Line Shell
---------------------------------------------------
 
[SQL]USER>>SELECT 1+2*3+4*5
3.      SELECT 1+2*3+4*5
 
Expression_1
65 
^^^^----------------------------------------------
[SQL]USER>>

.

Even the possibility of changing this elementary rule after 60+years
has the power and the risk of breaking millions of lines of code worldwide.
It's for people like you that are not willing to accept these rules that
the introduction of Embedded Python is encouraged. 

With the same mindset,
you may demand to revert from Italian, French Spanish, Portuguese
to pure Latin as spoken by Cesar. Or for French to Occitan ?

Just another strong argument for embedded Python
Or calling Py over $ZF() or CPIPE  for older versions

The code to convert XML to JSON is quite simple, just two lines.
The xmltodict. parse() method will convert the XML to a python object
that can then be converted to JSON.

How to convert XML to JSON in Python – Step by Step guide
(found by Google)

it is possible, but I'd rate it as highly inefficient. You have been warned.

working for objects and SQL

/// The company this employee works for.
Relationship Company As Company [ Cardinality = one, Inverse = Employees ];

Property Cname As %String [ Calculated, SqlComputeCode =
    {set {*}=##class(Company).%OpenId({Company}).Name }, SqlComputed ];