Kindle not recognized via USB on MacBook Pro running Sonoma

Hello!

I just grabbed a secondhand Kindle 7th gen (2014) running firmware version Kindle 5. 12.2.2.2 and for the life of me I cannot get it to connect via USB to my macbook pro running Sonoma 14.3.

I have CalDigit USB hub that is working just fine for other devices via USB (have tried hard drives and a MIDI keyboard). I have tried multiple USB-A to micro USB cables in multiple ports on the hub and nothing is causing it to be recognised. I do not have any other devices that use micro USB data to test with.

I have turned Settings>Privacy & Security> Allow accessories to connect to "Always".

I have restarted, both the macbook and the devices, and followed toubleshooting steps on and off this forum. Nothing. The device is charging by USB but does not show in finder, Amazon's Send To Kindle app or OpenMTP. I am out of ideas and useful google searches, and so once again I have Logged Onto A Support Forum.