What was the likelihood that Abraham and his original band from Texas would have come upon a scientist who had the key to reversing the plague, with the brilliant idea of engineering a virus that could kill the walking dead a second time - this time, permanently and really - and immunize everyone who had not yet become a zombie? It was the kind of idea a fan fiction writer might have come up with, and it was an ingenuous idea, indeed. But that's all it was, an idea.
Abraham's back story vividly shows why he was so vulnerable to signing on to Eugene's scheme. Abraham's family is gone, and Eugene gives him the opportunity to be of supreme use in this dying world - help make the world alive again. A mission like this was just what Abraham needed to live. It was irresistible.
Significantly, Rick and our central cast are not as vulnerable to such scams and delusions, because they have themselves, their literal and extended families, to motive them. But Abraham had no one, and Eugene came along at just the right time.
So where does the story go from here, with the attainable goal of a reversing virus now lying in ruins on that road in the South? It was such a good goal, I'm almost hoping that, someway, Eugene gets to tell his great idea to some team of scientists than can make it a reality, after all.
But, until then, or something as saving of the world comes along, Abraham, Eugene, and company are just another group of lucky, desperate survivors, who would do best reuniting with Rick.
See also: The Walking Dead 5.1: The Redemption of Carole ... The Walking Dead 5.3: Meets Alfred Hitchcock and The Twilight Zone ... The Walking Dead 5.4: Hospital of Horror
And see also The Walking Dead 4.1: The New Plague ... The Walking Dead 4.2: The Baby and the Flu ... The Walking Dead 4.3: Death in Every Corner ...The Walking Dead 4.4: Hershel, Carl, and Maggie ... The Walking Dead 4.6: The Good Governor ... The Walking Dead 4.7: The Governor's Other Foot ... The Walking Dead 4.8: Vintage Fall Finale ... The Walking Dead 4.9: A Nightmare on Walking Dead Street ... The Walking Dead 4:14: Too Far ... The Walking Dead Season 4 Finale: From the Gunfire into the Frying Pan
And see also The Walking Dead Back on AMC ... The Walking Dead 2.2: The Nature of Vet ... The Walking Dead 2.3: Shane and Otis ... The Walking Dead 2.4: What Happened at the Pharmacy ... The Walking Dead 2.6: Secrets Told ... The Walking Dead 2.7: Rick's Way vs. Shane's Way ... The Walking Dead 2.8: The Farm, the Road, and the Town ... The Walking Dead 2.9: Worse than Walkers ... The Walking Dead 2.11: Young Calling the Shots ... The Walking Dead 2.12: Walkers Without Bites ... The Walking Dead Season 2 Finale