I solved this mystery last night thankfully! I took out the needle to inspect it and a screw I had lost earlier found itself on the side of the needle, not allowing it to move. Once I put the screw back in place, I tried to get the meter to work but it still didn't budge. The red stick on the bottom of the prism is supposed to activate the electric charge by pressing two metal pieces together which conduct power from the battery to the needle. The two metal pieces were too far apart and the red stick wasn't bringing them together fully, so once I adjusted these everything works perfectly! I got a killer deal on my camera set up and had to do a little work to get it 100%.