Just jotting down a few notes from my build.
1. Installed macOS as detailed in the OP.
2. Ran MultiBeast to get audio working. Used AppleALC
3. Build was complete --------------- (At this point)
4. Partitioned the SSD to install Windows and configure the RGB software
5. Installed Windows and set up RGB lighting
6. Installed some drivers and updated the BIOS f10
7. Went back to boot macOS but it wasn't recognized. Which was expected since Windows wrote it's own Boot Manager to the drive
8. But then the drive wouldn't show within Clover nor within macOS Installer
9. Attempted to boot to Linux to wipe the drive entirely. Wiped it and it was still unrecognized.
10. Figured the BIOS update was the issue. But it wasn't. Looks like the SATA Mode was pegged at Intel Optane (one of the drivers and software I installed in Windows).
May want to add in your OP not to update to f10 yet nor to install the Intel Optane software/drivers. If you do, may need to manually set the Sata Mode back to AHCI.
All in all this was a great post with some good information. Just wanted to add this in for those edge cases.