A commercial flight will be MUCH less complicated and expensive than you'd find here. PNP is a message board for rescues, shelters, and pilots to connect for General Aviation transport; the only ground transport available is that which we must arrange ourselves to get animals to/from airports or to foster homes overnight.
I recommend Continental Airlines' Safe Pet Program for shipping unattended pets. Continental also sells crates for less than wholesale and you can get it when you ship the dog rather than shopping around town for one. What I like best about this airline is that once you call to make a reservation, the person you speak with will be with you until the dog arrives at the end of its flight. He or she will call when the plane is about to land and again when it's rolling to the gate. I think this will reduce your son's anxiety while his dog is on its way to him. You can expect to pay around $350-450 including crate. There is a new FL-based airline promoting pet travel too. I don't know its name but if you google "pet airline" you're sure to find it.
Compared to those options, to use PNP you would have to evaluate routing yourself, break the distance down into 300-mile segments, and then contact pilots along the route to see if they'll help you. You also have to locate a foster home or boarding facility at the various cities because a flight this long will require a number of overnight stays and may take several weeks to conclude. If you have to board the dog overnight or between pilots, and pay for transportation to/from airports, you can easily spend $1400. This is an extremely long transport and I'm afraid the chances that you'll find enough pilots (as many as 10-12) are pretty low.
If I may offer some advice, contact the breed rescue in your area and see what they recommend. The last thing that any rescue, or anyone here with PNP wants to see is a dog turned into a shelter, where it's survival is doubtful. Please avoid doing that with your son's dog. If you just can't get him on a commercial flight, consider making a poster to put in your vets office, and at Petsmart and places like that to rehome him.
I wish you, Jr, and Capone the best of luck.
North American Belgian Sheepdog Rescuearizonabsd@gmail.com