I keep thinking about how he told the daughter that her mom had two bottles of wine and went ghost crab hunting. What if he hurt her while kids were sleeping (after overhearing the phone conversation with her girlfriend), then disposed of her body on beach under brush, hoping that she'd "disappear" during the night. If her body was discovered, it could be chalked up as a stranger attack, drowning, etc. Seems like he was laying the groundwork to dispel foul play on his part. (Natalie Holloway story comes to mind.) As time went by, he panicked so loaded up the kids and headed north.
I've made that trek many times and the drive to Richmond from the Outer Banks is HORRENDOUS during tourist season starting on Friday afternoons - both directions. I am always frustrated and exhausted by the time I get to Richmond. The Outer Banks is congested, there are a lot of 2 lane stretches, and then out of Hampton Roads through Williamsburg to Richmond is bumper to bumper with crazy drivers and cops. I'm sure that he was stressed out with fear, questioning kids, etc. Pulled over in Richmond to collect thoughts and then came up with Plan B to put the daughter on a plane to Ohio and take off with his son. Richmond is the first big airport on the route. Norfolk and Newport News Airports are not easily accessible/visible from the route for someone not familiar with the area. Richmond's airport signs are prominent on the I64 / 264 route to Ohio.
He must have some conscious if he didn't hurt the kids. (Thank God.) He then regrouped in Richmond, and decided to at least get the kids home safe to their families before making his next move.
JMO.
Praying from NC for the family and friends.