😀👍👏

did you try Global-dump-to-SQL ?
it's not so fresh (from 2020) but just works for any Global

description is here Show Global by SQL SELECT

I like it!
I wonder if this would work also for Horse Races or Roulette or BlackJack or Baccarat.

The variable can't be the problem
BUT the typical default structure is /iris/sys/<instance name>/mgr/<namespace>

what is the method and the namespace you use to create the db ??

The "L" in your Open makes me nervous.
From the description, it seems to hang and wait for unlock not In IRIS but at OS-FileSystem Level.
The description of "L" seems to give some chance for such a conflict. 

suggested testing:

• Check the situation without "L"
• If there is a difference: find out who else may lock at OS level  

Objectscript uses double quotes for strings.
Single quote is Negation 
 'Sample Data  looks for variable  Sample >>> NOT Sample

/// example of an extra light output to CSV 
Class dc.SQLExport Extends %CSP.Page
{
ClassMethod content() As %Status
{
  set sep=";"
  set sqlStatement="SELECT ...... FROM ....."
    ,query = ##class(%ResultSet).%New()
    ,sc = query.Prepare(sqlStatement)
  set:sc sc=query.Execute()
  quit:'sc sc
  set cols=query.GetColumnCount()
  for col=1:1:cols { if col>1 write sep
    write query.GetColumnHeader(col)
  }
  write !
  while query.Next() {
    for col=1:1:cols { if col>1 write sep
      write query.GetData(col)
    }
    write !
  }
  quit $$$OK
}
/// filename should end with ".csv"
ClassMethod toFile(filename As %String) As %Status
{
  open filename:"WNS":1 
  else   quit $system.Status.Error(5005,filename)
  use filename
  set sc=..content()
  close filename 
  quit sc
}
}

You OTHER thought is supported by CPIPE
see Execute Server Commands from Caché / Ensemble / IRIS

good point:
there are only  17 rules referring to BUGS:

In total the quality check shows 106 rules

So there is more and I personally deeply disagree with some of them