Yes, it is that thin trace that goes to C22, but you don't need to mess with that at all. Solder a small jumper wire from that center lead of the POT there down to TP63.
TP63 is just below the Stick solder joints before you hit the shielded board there, they can be seen in your pic. That row of 3 TP spots, they look like small solder circles. Left to right, TP64, TP64 and TP68. Do not use a large gauge wire or hold the iron on the TP spot too long or you'll burn it off the board, then you'll have to solder to a via, which is even more difficult.
I use a 2.4mm sized chisel tip for just about everything I've done, and even for that repair you could use something larger than that and still pull it off if done carefully.