Tried and tested many times.
You need a hypodermic needle, the finest point size you can get, load with conductive paint as used for breaks in car window demisters. Inject the paint through the flexi pc at the connecting pads one by one. I usually do it with the set on, remember to use electrical safety precautions.
The downside, be carefull not to inject to much paint or it will short across to adjacent pads, then it's a new panel. I suggest you practice first, try it on an unusable panel watching for the paint just coming out under the pad.
You can use this method to repair breaks in flexi pc strips providing the strip substrate is not torn. Join the pads at both ends of the strip by laying down a trail of the paint following along the existing lines.
Strips torn in half can be repaired by applying sticky tape to one side, lay the trails, then sandwich with another layer of tape on top of the paint once it is dried and continuity tested between all pads.
Forget this method if you don't have patience, time, and steady hands.