interference of iShowU and Soundflower

I’m still trying to get Audacity working on my iMac (Catalina OS). Somehow I seem to have installed iShowU by accident, and have used the iShowU uninstaller (Several times!). I have also gone through the procedure of installing Soundflowerbed and Soundflower-2-0b2. However, only Soundflowerbed shows on my screen.
Now, in running Audacity 2.4.2 I cannot get rid of the iShowU in the input of the Device toolbar. Running the uninstaller and restarting have no effect on this. I can get to the point where the sound preferences is showing audio input from a Firefox tab, but ONLY if Sound preferences input is set on iShowU audio capture. Soundflower (2ch) does not show any audio input, and Audacity seems stuck on iShowU.
I therefore think that SOMEHOW I have to get rid of iShowU, because I can only see audio input in Sound preferences with that setting on both input and output, but cannot get Audacity to even monitor the sound.
Any help will be very gratefully accepted!

The official iShowU help explains uninstalling in detail:

I was going to suggest clearing the Audacity config files. They have a nasty habit of hanging onto stuff sometimes whether you want them to or not.

Was that a feature of Audacity3? An option to really, for real start over when you reinstall the program?