For Sierra, basic requirements for BCM94252 WiFi:
- FakePCIID.kext + FakePCIID_Broadcom_WiFi.kext
- 'fcvo' patch from the-darkvoid
- reboot, rebuild caches, reboot
Yes, and having those in place (although I use an SSDT over FakePCIID, same results with FakePCIID) results in me having working wifi with DW1560 up until I did a fresh install with updates to the last few security updates. The EFI folder didn't change. Clearly something is happening, but I guess it is just me. It sure seems like the fcvo patch is no longer applying even thought it is verifiably still valid for the latest binary.