Who is James Miller, Luke MacNamara, and Willard Douglass from The Zombie Survival Guide and what is their importance?

James, Luke, and Willard are Bostonian treasure hunters. They plan to loot Myan ruins in order to save a zombie from being buried alive. Note, they do not know he is a zombie but believe him to be human. MacNamara is killed instantly. James and Willard are bitten and presumed dead.