OK, so I ended up bypassing the HNC and EHNC all together. Being we need a reboot to occur before joining the domain, I created a powershell script to run on that first auto logon to take care of the name change. So the unattend names it with the * variable, then PS runs and pulls the current computer name, the asset from the bios, and serial from the bios and mashes them together and is working perfectly. Here is the script if it helps someone else gets started with their PS script:
#Rename the Workstation
$CurrerntComputerName = (Get-WmiObject -Class Win32_ComputerSystem -Property Name).Name
$SerialNumber = (Get-WmiObject -Class Win32_BIOS | Select-Object SerialNumber).SerialNumber
$AssetTag = (Get-WmiObject -Class Win32_SystemEnclosure | Select-Object SMBiosAssetTag).SMBiosAssetTag
$OSDComputerName = β$($AssetTag)-$($SerialNumber)β
Rename-Computer -ComputerName $CurrerntComputerName -NewName $OSDComputerName