Well I finally had a measure of success. I abandoned the guide and used Unibeast to make my installer. Worked the first time.
Now to figure everything else out.
These are the Kext I put on my USB-Stick (after the installation I added some more):
drwx------ 1 alexander staff 16K 24 Apr 00:03 AppleIntelKBLGraphicsFramebufferInjector_3e9x.kext
drwx------ 1 alexander staff 16K 24 Apr 00:03 FakePCIID.kext
drwx------ 1 alexander staff 16K 24 Apr 00:03 FakePCIID_Intel_HD_Graphics.kext
drwx------ 1 alexander staff 16K 24 Apr 00:03 FakePCIID_XHCIMux.kext
drwx------ 1 alexander staff 16K 24 Apr 00:03 FakeSMC.kext
drwx------ 1 alexander staff 16K 24 Apr 00:03 GenericUSBXHCI.kext
drwx------ 1 alexander staff 16K 24 Apr 00:03 Lilu.kext
drwx------ 1 alexander staff 16K 24 Apr 00:03 USBInjectAll.kext
drwx------ 1 alexander staff 16K 24 Apr 00:03 VoodooPS2Controller.kext
drwx------ 1 alexander staff 16K 24 Apr 00:03 VoodooTSCSync.kext
drwx------ 1 alexander staff 16K 24 Apr 00:03 WhateverGreen.kext
In drivers64UEFI I put these files:
-rwx------ 1 alexander staff 11K 8 Dez 2018 ApfsDriverLoader-64.efi
-rwx------ 1 alexander staff 5,5K 8 Dez 2018 DataHubDxe-64.efi
-rwx------ 1 alexander staff 22K 8 Dez 2018 EmuVariableUefi-64.efi
-rwx------ 1 alexander staff 22K 8 Dez 2018 FSInject-64.efi
-rwx------ 1 alexander staff 24K 17 Jun 2017 HFSPlus.efi
-rwx------ 1 alexander staff 23K 18 Apr 18:53 OsxAptioFix3Drv-64.efi
-rwx------ 1 alexander staff 23K 8 Dez 2018 PartitionDxe-64.efi
-rwx------ 1 alexander staff 4,3K 8 Dez 2018 SMCHelper-64.efi
-rwx------ 1 alexander staff 21K 8 Dez 2018 UsbKbDxe-64.efi
-rwx------ 1 alexander staff 9,3K 8 Dez 2018 UsbMouseDxe-64.efi
Ive also used the mentioned plist.
Did you follow the necessary steps to unlock your BIOS? I also removed the WLAN-whitelistening (replaced the built in Intel with a Broadcom).