At this point I see the main issue with the father is he had a planned recon/scouting mission and was planning to return to their "camp" at 1:30pm. He never returned. That doesn't sound good and add to the fact that he left the road and traversed into a creek and ditch area.
I am not sure how rugged the terrain is there...but I can assume it is pretty tough.
I hope he was injured in a fall or something. He may have fallen into water as well.
According to the interview with his wife at the hospital he really didn't have good clothing to hike out in (specifically he was wearing tennis shoes).
Maybe he decided to keep going because he thought if he went back they would never be found. Hopefully he has found some type of shelter and they will find him alive.
Yikes I just re-read what I wrote...
I certainly didn't hope he was injured.
It should have said: I hope he wasn't injured in a fall...
Please accept my apology for my error.