I am not near any macOS machine right now, but there is no need for Inject ATI, that is a legacy option, WhateverGreen.kext does the automatic injection or and extra boot-arg / configuration specific to it.
Emuvariableuefi.efi is not needed if you did read post #1, don't put things that are not listed.
MacMini 6,1 is the SMBIOS in use with my files, others will affect USB Ports and other things that may break.
I don't have dedicated GPU so i can't say more than that about it, will take a look at files later.