Thank you for your true 'Forum Spirit'. As you can see , you are one of a few who has been able to successfully install Mojave on a 300 Series board without too long a troubleshoot lasting for days. Your detailed illustrated post will be searched by many and would contribute a lot to the Hackintosh community.
It will be a good idea to Clone your Disk. If you are interested to use the Freeware(DonationWare) Clonezilla , you can check this brief illustrated post ->
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In all difficult installation, I clone the successful Hard disk onto a cheaper disk of equal or bigger size using Clonezilla and then also try a fresh install on another Cheap disk using a USB Installer taking images from its own Partition and Format , creation of UEFI USB Installer, Installation and editing of CLOVER/kext/other, drivers64UEFI and all the SECTIONS of config.plist, BIOS Options screen shots, CBM screen and its Options Submenu screen shots, Verbose boot Screen shots , MojaveUtilities_DU and Mojave Hard disk Installation Screen shots, System Installation screens, Desktop and System Report_Hardware Screen shots, System Preferences screen shots ( networking , Sound etc) . This when properly edited becomes a complete Mojave Installation Manual for your Hackintosh or Muti-boot System for yourself and to a lot of others through this Forum.
Please Prefix your Post [SOLVED] to make it a useful search term.
Good luck.