It is probably related to the environemnt like desease and/or food items, hydration ect. Could be several factors or it could be the wildcaughts just look like wildcaughts.

Either way inbreeding depression has not been proven in several generations of the morphed cal kings so why would it effect isolated wild pops?

This is a goog question for realherper who has seen more cal kings in commercial areas than anyone alive.....

....hubbsie are you out there?