Macos Catalina 10.15.5 on MacBook Pro and FTDI driver 2.4.4 - Procedural workaround for Apple FTDI driver (seemingly) interfering with FTDI's driver causing intermittent operation with Moonlite focuser

The procedure for dealing with the Apple USB driver interference bug is:

1. Reboot so you have a 'clean' system. USB device is connected for reboot.

2. On boot we have duplicate devices:
Steves-MBP:~ sjf$ ls -l /dev/*usbserial*
crw-rw-rw- 1 root wheel 18, 9 30 May 13:39 /dev/cu.usbserial-4
crw-rw-rw- 1 root wheel 18, 1 30 May 13:39 /dev/cu.usbserial-AH0741BL
crw-rw-rw- 1 root wheel 18, 8 30 May 13:39 /dev/tty.usbserial-4
crw-rw-rw- 1 root wheel 18, 0 30 May 13:39 /dev/tty.usbserial-AH0741BL

3. Unload the Apple driver (even though utilities seem to show it is not loaded!) with:
Steves-MBP:~ sjf$ sudo kextunload -b com.apple.DriverKit-AppleUSBFTDI ; echo $?
Password:
0 <---- Return code seems to suggest no error which means it must have been loaded (or is that just the return from sudo?)...anyway...
Steves-MBP:~ sjf$

4. Physically disconnect the USB device:
Steves-MBP:~ sjf$ ls -l /dev/*usbserial*
ls: /dev/*usbserial*: No such file or directory <--- Yes, it is gone
Steves-MBP:~ sjf$


5. Reconnect the device, and now we have what I would have expected in the first place with no duplicate devices:
Steves-MBP:~ sjf$ ls -l /dev/*usbserial*
crw-rw-rw- 1 root wheel 18, 1 30 May 13:45 /dev/cu.usbserial-AH0741BL
crw-rw-rw- 1 root wheel 18, 0 30 May 13:45 /dev/tty.usbserial-AH0741BL
Steves-MBP:~ sjf$

6. ...and now the device is working happily, which to me says the Apple driver is interfering somehow even though it says it is not loaded.

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