Mac OS X 11.6 not recognising Yamaha Steinberg USB driver 3.05

I’m running Mac OS X 11.6 on a MacBook Pro Retina, 13-inch, Mid 2014 with an Intel i5 processor.
I have installed the Yamaha Steinberg USB Driver 3.05 and UR Tools for UR V2.2.2
The USB driver does not show up in the Audio MIDI Setup panel.
dspMixFX_UR44 recognises the connected UR44.

Researching this problem suggests that the USB driver has failed to install. Though all the articles talk about Mac OS X 10.11 or earlier, or specifically Macbook Pro Apple Silicon processors.
I have uninstalled and reinstalled it and the Tools package several times.
I have checked the Security & Privacy panel, but there is no notification asking for acceptance.

The Yamaha USB driver appears in the Applications folder.

Is this a compatibility issue with Mac OS X 11.6 that you are currently working on?

Screen Shot 2021-10-23 at 1.20.32 am

So, in case anyone else encounters this, I’ve rectified it.
My UR44 was missing from Audio MIDI Setup on my Macbook Pro.

I had already followed this article without success:

Mac OS X wasn’t allowing the USB driver extension, but also wasn’t creating an alert for me to allow the extension in the Security & Privacy panel in System Preferences.

Running this command in Terminal allowed the extension temporarily until the laptop was restarted:
sudo touch /Library/Extensions

The solution was to disable the System Integrity Protection:

Uninstall Yamaha USB Driver.

Restart/Power on your Mac (Apple > Restart / Shut Down).
Recovery Mode: Hold down Command-R until the Mac logo appears
Enter Password
Wait for OS X to boot into the OS X Utilities window.
Run this command in Terminal:
csrutil disable


Reinstall Yamaha USB Driver 3.05


Open System Preferences → Security & Privacy
Unlock changes
Reauthorise Yamaha Corporation extension.