One of my daughters lives in Va. and I've driven there and back to Louisiana several times. The drive down through the Shenandoah Valley is rural and not like it would be on an interstate route. You can come down through Tennessee and Mississippi to Louisiana. Then down to Lake Charles and over to Houston.
Easy to get from Houston to Galveston, Texas. Major cruises depart from Galveston. Check it out.
I'll bet JLM has changed his appearance drastically and was going to attempt to leave on a cruise ship. That would require a fake ID and passport. It's possible.
OR JLM could have been hoping to go to work on a fishing or shrimp boat. You don't go to Mexico via Galveston, IMO. You go from Houston over to El Paso and cross over the Mexican border there.
My guess is that he murdered Hannah and knew he would definitely be arrested for murder if he hung around Va.. He may very well have done much more than murder Hannah and knew he was going to be found out.
JLM had connections and someone helped him leave. Someone helped, IMO. Had to have changed his appearance also!
Now where is Hannah?????