After having watched the crocs, up close, for many years now (we had one that lived under and beside our pier in San Pablo, I can say that I have yet to see one that was scared of a dog, person or even a large dump truck. There are 5 good sized crocs in the WASA pond now. I keep my dog in our fenced yard to keep her safe. There is also a croc that swims by our beach each morning - so we don't swim in the sea right off shore any more.
King is a lovely, sweet tempered pup. He could quite easily have wandered off, following kids down the beach. He could also have met a brave croc.
We are all keeping an eye out hoping we will see King so he can be returned home. Scott must be terribly heart broken.
BTW Peter is probably one of the most protective pet owners I know - he loves his Charlie.
And yes JZB pedigree dogs are stolen often and resold on the mainland. It would be worthwhile checking in areas on the mainland. There are very few Great Danes in country and only a few families would consider owning one - imagine the food bill, and the doggie mines in the back yard!