Well clearly the tangs on the driver collar won that one
As a thought (if you haven't already put it back together again), would be to
shape two more indents into that nylon gear collar at 90 degrees to the broken out pieces, then it would be a blind alignment to pick up the tangs to enguage the two new
cut-outs in order for the worm and gear to again drive the new cable.
Would be easily assesed as a working fix, or otherwise, by
rotating the
speedo dive gearbox (for want of a better discription), around the wheel hub prior to returning the wheel into the stanchions, to see if the drive is working.
Worth I consideration I would think as there seems to be plenty of remaining gear skirt to work with.
Cheers the can :-)