I DID IT!!!! Ever since I graduated I avoided doing anything to fix the one FSR that was not working properly, and I finally fixed it! I unplugged everything, took out the PCB, soldered the resistor and a few connections, cut the FSR off of its original connections, and re-hooked it up to the additional LIS3DH A2 pin. And I did it all without damaging anything else!
I plugged the original FSR data wire (that is going into the mux) into ground, and for that I thought it was too risky to solder that close to the plastic GLOBE. So I had used a lot of electrical tape and a jumper. It is not elegant, but it works. Something interesting is that grounding that 16 pin also fixed the bleeding from the 13 pin going into the 15 pin.
It was also the first time that I got to use my new heat gun on the heat shrink. So much fun!
Now I need to o back to my patches and update them all to include this sensor!
If you are looking for a summary for my Masters thesis, it is here.