Hello!
This is my first post in this forum.
I would like to confirm that I had great success using the guide provided in this thread on High Sierra 10.13.4. I have used
this Broadcom BCM94360CD adapter (I am not advertising; just letting people know that this one actually works), and everything works fine
OOB (WiFi, Bluetooth, continuity, everything), just like with a real iMac (no additional drivers needed, nothing). For your information, I am using the 14,2 SMBIOS,
although my processor is newer.
Before I got the Broadcom "native" adapter, I was using a Realtek USB WiFi adapter, and I could not make iMessage work; Apparently, as P1LGRIM has nicely pointed out, you need your adapter to be recognized as native by MacOS. Also, the whole setup process was conducted
exclusively over WiFi, with a working, also native Ethernet connection being present in the system, but not utilized at all.
Hope the above helps someone with a similar system.
Thanks for the great tutorial!