Karabiner Elements Driver no longer activates

Like many others here, I am facing the problem of the Karabiner Elements driver not activating on Catalina 10.15.7.

I have tried everything I could find on this forum ... reinstalling multiple versions (12.10, 13.0, 13.3) -- none of it works. No amount of reinstalling, in safe mode or otherwise, makes the "Activate driver" button work. This is what I see:

However, opening Preferences shows nothing:

My log fills up with this error:

[2021-02-04 17:52:37.016] [warning] [virtual_hid_device_service] driver_version_ is mismatched: client expected: 10300, actual dext: std::nullopt

Is there a way for me to "allow" the drivers via the command line, so that I can bypass this issue until it's fixed? If so, please share what the command might be. I desperately need my Karabiner back! ;)