The PC thing could spread:
how about
niggle
niggler*
niggling
dark
darkness
darkenning
darkly*
packer*
packing
chin
chinny*
* are very dangerous to say out loud on public transport or in the bar.
Joking apart, I revisited Woodhall Spa yesterday: memorial, Petwood Hotel for bar snack and a look in the squadron bar. The dog thing does seem very insignificant and I cannot think the Chastise crews would have given a stuff about the dog's name. The code word is a bit different, that is rewriting history rather severely.
Just get on and make the film!