Check out the Wifi/BT guide:
Broadcom WiFi/Bluetooth [Guide] WiFi and Bluetooth working out of box on macOS with Apple branded Broadcom BCM94360. Enables specific half mini and M.2 BCM94352 on macOS with methods described below. Credit: RehabMan This thread does not support: macOS/Continuity Atheros/Qualcomm...
www.tonymacx86.com
BrcmPatchRAM installs/injects the firmware. BrcmBluetoothInjector.kext (for 10.14.6 and below) only injects bluetooth to see if it works but does not inject firmware. If AirportBrcmFixup.kext is not installed correctly it's possible that your wifi works OOB and does not need any WiFi kexts.
You can see what kexts are installed by looking in your Library/Extensions (L/E) folder.
Try the Bluetooth kexts attached which fixed Bluetooth for me in Catalina with my XPS 9570.
If those don't work try deleting all wifi/bluetooth kexts from Clover/Kexts/Other folder EXCEPT BrcmBluetoothInjector.kext and see if anything changes, that way you know at least which kexts are not working correctly.