You can d/l SATSMARTDriver from https://github.com/kasbert/OS-X-SAT-SMART-Driver.

Click on the highlighted item, and then click on "Download" on the next page. You may have to go to System Prefs > Security & Privacy > General to allow installation.

I've got no idea if it'll help, but it can't hurt to try.

As I said earlier, when I first installed DriveDx it couldn't see my external until I went through this procedure.

The new Great Equalizer is the SEND button.

In Memory of Harv: Those who can make you believe absurdities can make you commit atrocities. ~Voltaire