Please forgive me if this is obvious or poorly worded - I'm struggling here and am not too tech literate.
Some quick background:
Thanks a ton in advance
I understand the Intel® NUC does not boot to the operating system and you are getting blinking lights when powering on. Sorry for the inconvenience.
It does seem to be a problem with the Intel® NUC itself.
Have you tried BIOS recovery?
This recovery BIOS might be able to help if the BIOS chipset does not allow the computer to post or boot.
Please try downloading the *.bio file https://downloadcenter.intel.com/download/26602/BIOS-Update-GKPPT10H-86A-?product=71274 here
Place the file onto a USB flash drive. The USB does not need to be formatted. I recommend checking instructions for BIOS recovery at this https://www.intel.com/content/www/us/en/support/articles/000005532/mini-pcs.html link
If this fails, please bear in mind the board replacement for this kit is D33217CK and if you would like to search for the board, this is the part number BLKD33217CK
Hope it helps,