I’ve botched a DOS batch file which does the job – the coding is not tidy by a long way but it does the job! Just putting it here in case anybody else finds it useful.
@echo off
set uber=%1
set uSID=
Set foobar=
for /F “tokens=1* skip=1” %%a IN (‘psloggedon \%uber% -l -x -nobanner’) do @set foobar=%%a
set foobar=%foobar:hiew2k=%
for /F “usebackq delims== skip=1” %%i in (psgetsid.exe \%uber% %foobar%
) do @set uSID=%%i
psexec -nobanner -accepteula \%uber% -s reg add “HKU%uSID%Keyboard LayoutPreload” /f /v 2 /t REG_SZ /d 00000491
psexec -nobanner -accepteula \%uber% -s reg add “HKU%uSID%Keyboard LayoutSubstitutes” /f /v 00000491 /t REG_SZ /d 00000809