Okay so I figured out what was going on. I had two micro-usb cords, one was connected to my RaspberryPi and one to my laptop. The issue was with my micro-usb to the RaspberryPi, it was powering the Teensy LC but not reading it.

I switched the cords and it started working on the RaspberryPi.

You can imagine how frustrated I was, given I am new to all this.

Thanks for your help Mitu!

The thing is, I've tried everything.
Last night, I had it where the left stick worked, except it would not go up.
The right stick would open the configuration menu, in addition to firing.
Some how I got it reset, but now I can't get the left stick to work, and from what i'm reading, that's the one that should by default?

@TheMervinator I'm having the same issue did you ever find a solution?

@bassholio which n64 emulator?