Civilian here, some questions on why it took a while to find.
No ADSB? Thought it was mandatory around San Diego. No ELT? No Sat tracking (everything I fly corporate or commercial has sat tracking)? Even an iPad with Foreflight would have given them plenty of warning they were about to eat dirt, maybe not sanctioned but who wouldn't throw one in their bag?
Flown IFR lots in winter, icing is pretty rare - tips run warm, and usually you climb out of rain, through a sleet layer into snow. Nothing sticking to the blades.
Robust aircraft, trained crew, I'm a little surprised at the discussion on weather that I wouldn't have thought would be a factor.