So a quick update, it was the tube. Replaced it with a Tung-Sol 12AU7W and both sides sprung to light.
I had mentioned that I had a friend come over to help me diagnose. Turns out one of the LED's essentially wasn't allowing current through it (if I remember correctly), and I had messed up the volume potentiometer trying to wick off excess solder to redo the connections. So I have replaced the broken LED and have an Alps RK27 Velvet pot on the way to replace the one I butchered.
Essentially had three issues wrapped into one giant mess. But seems to be on the up and up.