Recently I was trying to get a WDS server PXE Booting using Legacy and UEFI booting. I followed the DHCP guide here Legacy worked however UEFI was not working. I double checked on the WDS server for the 67 Option with a file share and in

\\%IPOFSERVER%\reminst\Boot\x64

wdsnbp.com existed but no wdsmgfw.efi

Running a rebuild of the boot files also did not fix this for some reason , in the end I copied the file from : 

\\%IPOFSERVER%\c$\Windows\System32\RemInst\boot\x64

and it resolved the issue