There is no check box for that on a scripted installation that I can find

It may be due to that you are using OEM media.

Any other suggestions?

Yea, lets step thru the batch files to see what is broke.
First hover over your scripted install and you will see in the bottom of the browser an boot image id. Using file explorer go to \\ikbox\peinst\scripts and get the scripted_install_ID#.bat and post that.

@echo off
set Option=Prompt
set GoToStep=1
set OS=20
Y:
echo Running Install Script for Test 2
start /wait %windir%\system32\mshta.exe Y:\hta\rpc_start_scripted.hta 8

if not '%1' equ '' set %1
if not '%2' equ '' set %2
if not '%3' equ '' set %3
if not '%4' equ '' set %4
if not '%5' equ '' set %5

rem preinstallation tasks
cscript Y:\hta\getkuid.vbs

:step1
set GoToStep=2
echo Executing diskpart /s create_single_partition.conf
cd Y:\preinstall\1 && diskpart /s create_single_partition.conf

if ERRORLEVEL 1 goto PreAbortContinue

:step2
set GoToStep=3
echo Executing call format_c_as_ntfs.bat
cd Y:\preinstall\2 && call format_c_as_ntfs.bat

if ERRORLEVEL 1 goto PreAbortContinue

:step3
set GoToStep=4
echo Executing call install_vista_2008_7_8_2012_mbr.bat
cd Y:\preinstall\4 && call install_vista_2008_7_8_2012_mbr.bat

if ERRORLEVEL 1 goto PreAbortContinue

:step4
rem run windows setup
Y:\source_cds\10\setup.exe /unattend:Y:\sifs\8.xml /m:Y:\oemfiles\8\$OEM$ /noreboot

rem determine system drive
for %%I in (Z W V U T S R Q P O N M L K J I H G F E D C) do (
if exist %%I:\KACE set KACEPATH=%%I:
)

rem Dump K1000 Inventory Data
md %KACEPATH%\KACE
start /wait %windir%\system32\mshta.exe Y:\hta\rpc_dump_k1000_inventory.hta boot_image_id=8 %KACEPATH%\KACE\k2000_deployment_info.conf

rem copy drivers

:step5
REM Copying KUID and drivers

cscript Y:\hta\copykuid.vbs
cscript Y:\hta\copy_drivers.vbs

if not '%OFFLINE_DIR%' equ '' (if exist T:\%OFFLINE_DIR% (rmdir /S /Q T:\%OFFLINE_DIR%))

rem reboot

cscript Y:\hta\kreboot.wsf

exit 0

:PreAbortContinue
if (%Option%) == (Yes) goto end
if (%Option%) == (No) goto step%GoToStep%
cscript /nologo //Job:PreInstallTaskFailOptions Y:\hta\prompt.wsf USER_SCAN_FAIL:%FAILEDUSERS%
if NOT ERRORLEVEL 1 goto step%GoToStep%
goto end

:PostAbortContinue
if (%Option%) == (Yes) goto end
if (%Option%) == (No) goto step%GoToStep%
cscript /nologo //Job:PostInstallTaskFailOptions Y:\hta\prompt.wsf
if NOT ERRORLEVEL 1 goto step%GoToStep%
goto end

:RsaPreAbortContinue
if (%Option%) == (Yes) goto end
if (%Option%) == (No) goto step%GoToStep%
cscript /nologo //Job:PreInstallTaskFailOptions Y:\hta\prompt.wsf USER_SCAN_FROM_RSA
if NOT ERRORLEVEL 1 goto step%GoToStep%
goto end

:end
exit 6

great. lets check the source folder and xml file you are calling in step 4
I want to see if all the things you are calling are there
sub \\ikbox for y:
Y:\source_cds\10\setup.exe
I posted my source folders in a new answer cannot add pics to comments

/unattend:Y:\sifs\8.xml
see what this file is, you are calling it as the answer file.

/m:Y:\oemfiles\8\$OEM$
make sure this folder exists

If all this looks good lets boot into pxe kace menu and open a command prompt and then go to y:\source_cds\10 and run the setup.exe

All of those files do exist in their respective directories. The 8.xml file is an answer file created with the scripted installation wizard.

that would be my guess then, could be something bad in the oem files also but I would lean towards a bad entry in the answer file. You can view it in the deployment and cut and paste it out. I Tried to copy the file from the server to notepad but it ran it together all on one line for me.

any progress?