Looks like you will have to remove the brass tube that passes thru the hull...if it does.
Is the entire tube inside the hull and exit thru the transom? Or does it pass thru the bottom ?
Either way, you will need to cut the old one out... a dremmel tool works good.
Then the new tube will need to be formed to match the old one, and then glassed back in place. A good epoxy or fiberglass resin is what you need here...and a little glass cloth.
Auto parts stores usually sell small resin and cloth kits in the body repair section..
Brass tube can be bought online, K&S Brass
or try home depot, lowes, Ace hardware.
Just get the proper size for your cable.
Install a new cable, and you should be back in business....
This is just my opinion here, but if that wheel collar on the cable is not balanced, I wouldn't run it.
Just a tiny bit of imbalance at 30K RPM can impart a huge out of round load... cable starts to whip,, rounds out the tube, and here you are...either that or push it up against the collet when you tighten it down, the motor bearings will better deal with it. .
Good luck !