Did not have time to read all the threads here. I got my Congo with me when I came here. I did not come from as far as you but I could never leave him behind. The climate here is great for dogs, not too hot and if they are used to sleeping indoors, whats better than a central heated place? or a fireplace?
My friend got her 3 dogs from Canada. She got them on a ship. Her husband came by plane and she came with her dogs by ship. I am sure it is less traumatic although longer journey and you can be with them all the time.

Your old dog would be devastated to change owners after sucha long time or be separated from his shepherd friend. I would opt for a ship journey. It's cheaper anyway and you could make it a nice relaxing journey for yourself, have your hubby prepare a fence for them in the garden by the time u get here