you describe 2 different record layouts that reside within the same storage 
#1 - just a name
#2 - a name + a "transferred" property

depending on the situation you use either layout #1  or layout #2 for INSERT
reading might be OK for layout #2 in both cases.

Caché once had a somewhat similar sample with Person
and Employee extending Person. 
available here: https://docs.intersystems.com/iris20241/csp/docbook/Doc.View.cls?KEY=ASAMPLES
this Repo:
https://github.com/intersystems/Samples-Data/tree/master/cls/Sample

eventually better to check for longer lists

USER>s x=$lfs("Purple,Black,Yellow,Pink")
USER>s y=$lfs("Red,Green,Orange,Yellow")
USER>f z="y","x" f i=1:1:$ll(@z) i $i(dif($li(@z,i)))
 
USER>zw dif
dif("Black")=1
dif("Green")=1
dif("Orange")=1
dif("Pink")=1
dif("Purple")=1
dif("Red")=1
dif("Yellow")=2
 

looping with $o() over dif() allows programmatic check

nothing official

Once upon a time ...

• there was an operating system named VMS
• running on computers named VAX and ALPHA
• The syntax to access a file was  drive:[directory] 
• it's the same structure used by RSX-11/M, RSX-11/D, RSX-11/S on PDP-11 processors

So on drive DUA1  you refer to director TEST3 

default super Server port = 1972   !

set int = +testingID

same using USE 0:(:"/ECHO=0"")   and  USE 0:(:"/ECHO=1"") 
or
Use 0:(":"S") and Use 0:(:"N")   for "silent" and "normal"
more docs

my private hack for this situation:

ClassMethod MyMethodPost() As %Status
{
    $$$LOGINFO("JobId: "_$JOB)
    kill ^%kurro
    set ^%kurro(0)=$JOB
    for  {hang 20 break    quit:$get(^%kurro) }
#; just hang around until ^%kurro =1
    ..... 
    Quit $$$OK
}

You can map PACKAGE [aka. SQL Schema] to another Namespasce (not a single table)
e.g. Bna.Utils to namespace %ALL or just to a specific namespace
so you have Table and Class  (= the code) available.

If you want to share also DATA  you need to map also  the related Global 

ChatGPT is just stupid and has no idea of IRIS / Caché
A TABLE will by default never have the same name as the GLOBAL that stores the content
>>>> HS.IHEX.RecordHistory and the global ^HS.IHEX.RecordHistory  <<<<<
HS.IHEX.RecordHistory is definitely not a handcrafted table.

Hi @Daniel Aguilar 
for every DB you have a default collation that is tied to DB:
you can see it in SMP  System > Configuration > Local Databases > Database Properties

this is the standard.
If the collation of your source server is Spanish, German, Fench, , .... 
the DB may have used this national collation as default.

On your target serve you need to have this collation to be installed.
in SMP  System > Configuration > Locale Definitions you see what is installed on your Caché instance

You may need to add the missing collation table to your Caché instance:

•  iristerm does NOT support ssh
• you need to run ( + install ?) a SSH service in your  Linux SUSE 15 VM 
• next, you connect from Win10 over any SSH terminal client (e.g. Putty, ...) to your SuSe VM console command line
• there you can run iris session ...........  (the Linux equivalent of iristerm)

Just as described in your question

there is a basic misunderstanding:

inside the <CSP:WHILE...> block you are in HTML context
but you issue instead JavaScript >>>> which just prints it out.
To illustrate this see this simple example:
But changing to JS_context solved my simple demo with alert();
 

<csp:WHILE CONDITION="resultSet.Next()">     

 <!-- xValues.push(#(resultSet.Get("StatsDate"))#)
  yValues.push(#(resultSet.Get("Value"))#) -->
  
 <p>#(resultSet.Get("StatsDate"))#<br>#(resultSet.Get("Value"))#</p>
 
 <script LANGUAGE="JavaScript">
 alert(#(resultSet.Get("StatsDate"))#+'>>>'+#(resultSet.Get("Value"))#);
 </script>

</csp:WHILE>

the correct syntax

            ccontrol [ run OR console OR cterminal ] <instance name>
                        Runs Caché in programmer mode with
                        [ no-device OR console OR cterminal ] for $Principal

try this dirty hack:

• create your JSON object using "_"  
  • Property "client._id" As %Integer [ Required ];
  • Property "client_firstName" As  %String [ Required ];
  • Property "client_lastName" As  %String [ Required ];
• create your JSON_body = { "details":{ ....} }
• before sending use $TRanslate(JSON_body,"_",".")

n i f i=1:1:20 w !,$$save(file,glob) s id=^TEST zw id 

it looks like magic and the issue is independent of Global name
for testing, I would suggest this extension to the loop.
zw also shows any $Lb() in readable format
6, 7, seem to break sometimes ??

you are not quite correct:

abstract class %CSP.Stream is a base class for

• class %CSP.CharacterStream extends %GlobalCharacterStream, %CSP.Stream
• class %CSP.BinaryStream extends %GlobalBinaryStream, %CSP.Stream

you decide which one to use
Where is the problem ?