Shielded cable sucks to splice! We use a lot of sensor's on equipment that run shielded cable and we have tried to splice them, just like he did in the video, with very little success. Yes they will work after they are spliced but that splice changes the way that sensor reads. They are never as accurate as when that cable was whole, so anymore we just run a new cable when we find a bad one. A variation in signal on a potentiometer or a temp sender can do some strange things. Granted this is a different application than a transducer but I would still be pretty hesitant to splice it myself.
What's the cost of a new one? Splice it for a quick fix to get you back on the water but in the long run I would replace it.