Thanks so much for trying to help. As stated in my original post, I have tried bluetoothctl, but it doesn’t seem to be working as it’s supposed to.
I get the [bluetooth]# prompt, but it’s not blue even when my device is in pairing mode, and I can’t type anything at the prompt. There is a flashing cursor, but typing does nothing. I can only type command C to restore the command line.
Hopefully somebody can find a clue in all of this. Again, my BT dongle does work, and I have a PS3 controller working just fine via BT. However, I’m trying to connect an 8bitdo controller and my system’s Register and Connect is not working (as described in OP), and I can’t utilize bluetoothctl as described here and in the OP.