I just got it booting again:
I got my usb mojave installer, update Clover to the latest version (r4910), Lilu, WhateverGreen, AppleALC, your post installations files, set up my config.plist with almost same settings as before (same Serial Number, SMBIOS, etc). I just disabled IGPU in BIOS again and also setup Clover config the same way you say in the spoiler about pro video/audio apps.
It booted perfectly from the USB.
But now, I can't login. After I insert my password I got the spinning icon forever. Already tried to boot in Safe Mode and it's the same. The only way it boots is when choosing Guest User.