The MEDEVAC helicopter flew over mountains fully loaded with Moss and three other wounded, racing the clock. Moss' best chance of survival was to get advanced medical care within one hour of his injury. Trauma surgeons call it the "golden hour." But Moss' had already ended.
Radio dispatches let the trauma team know that they had one critical patient coming whose blood pressure was dropping and heart rate was dangerously high. But reports of the true nature of Moss' injury had not reached the closest medical facility at the Orgun-E base -- a former goat shed transformed into a rough field hospital. They were told it was "shrapnel injury." The aid station had two doctors, Maj. John Oh, a general surgeon, and Maj. Kevin Kirk, an orthopedic surgeon. At this point it wasn't clear which Moss needed most -- a surgical team or a bomb squad.
It was only when Oh started cutting away all the bandages that "Doc" Angell had delicately wrapped around the RPG that he saw what they were facing.
"It had fins coming out of the left side of his body and had a big bulge in the front of his right thigh," Kirk said.
Still conscious, Moss remembers the faces dropping in shock as they took in the sight.
Incredibly, both Oh and Kirk had drilled for this exact scenario, because the Army has a protocol to handle patients with unexploded ordnance in them.
"You're actually not supposed to bring them into an aid station," Oh said."And actually, he wasn't supposed to be flown with the other patients either."
According to the "War Surgery Manual," Moss should have been placed far away from other patients and operated on last. If procedure had been followed, Moss would likely have bled to death, but the doctors felt compelled to save him.
Then Pvt. Moss had another life-saving break -- Staff Sgt. Dan Brown, the explosives expert who spends his time disposing of bombs and captured weapons, was on the base. In his spare time, Brown had been watching an episode of ABC's "Grey's Anatomy" about a patient with an unexploded grenade in him. In that story, the bomb technician is blown up. Brown was about to play a leading role in his own non-fiction drama.
Brown, shocked to see that Moss was still alive, confirmed that they were dealing with an RPG. Moss' life hung on whether or not they would remove the rocket.
Brown explained the different scenarios of what could happen. The worst case was that they would all become "pink mist" -- everyone in the room would be killed. But to identify how much explosive power they were facing, they needed an x-ray to determine whether the RPG's warhead was inside Moss. Their notoriously temperamental x-ray machine malfunctioned, and it wasn't until the third attempt that they got a decent image.
The doctors and Brown were relieved by what they didn't see. The deadliest part of the RPG -- the main explosive charge -- was not in Moss. But their relief diminished when Brown explained to the surgeons that it would still have enough force to kill Moss and destroy their hands.
At that point, Oh ordered everyone except the critical staff out of the aid station, the two doctors and three surgical staff remained. They all knew the risk they faced.
"I looked everybody in the eye and said, 'You guys understand what's going on here, right?' And I knew everybody heard me, but nobody said anything. They just kept doing their jobs," he said.
Oh told them it was okay to leave -- but nobody did. With no words exchanged, each had decided to risk their life to save Moss.
Extreme blood loss had caused his heart to stop. Unable to do chest compressions for fear of setting off the round, they gave him epinephrine. His heart soon restarted and they could finally operate to remove the RPG.
Sgt. Brown used an unusual instrument to gently remove the RPG's tail fins -- a hacksaw. The surgeons reached inside Moss, steadying the still lethal rocket, inches from the soldier's beating heart. They then gently eased the rocket out, with the detonator aimed at Brown's flak vest.
Brown quickly walked out of the aid station to a bunker and detonated it. The sound of the explosion thundered through the base. As the surgeons closed up Moss' incisions, Sgt. Brown sat down outside to collect himself. Finally, the impact of the drama hit him.
"I started shaking. I just sat there. I knew I did everything I could to help him live. And that was very, very intense for me after the fact," he said.
In a matter of days, after stops at hospitals in Afghanistan and Germany, Pvt. Moss was rushed to Walter Reed Army Medical Center in Washington, DC. There his wife, Lorena, saw him for the first time and it was almost too much to bear.
"He looked very vulnerable. I went in, and ... I walked away. I couldn't stay in the room. I broke down outside in the hallway," she said.
Moss' pelvis was shattered, his internal organs were severely damaged and he was unable to walk.
For Moss, this was another challenge in a lifetime of obstacles. Raised by family friends after a tough childhood, he had become a high school football standout, got into college, got married and had a family.
As broken as Moss' body was, he focused from the very start on recovery. He said he didn't need a doctor to tell him if he'd be able to walk again.
"I told [the doctor] ... I could feel my feet, I'm going to walk again. Told him just like that," Moss said.
For his wounds in combat, Pvt. Moss had a Purple Heart coming. But he wanted to wait. It was important for him to be able to stand to receive it.
He underwent four major surgeries followed by intense physical therapy. Pvt. Moss' recovery was steady … moving from a wheelchair to a walker to a cane.
"I wanted to walk and get my medal, I wanted to stand up, to let them know I fought hard to get where I came from," Moss said. "They say 'Army Strong' [and] I wanted to be an example of that, and I was. So I stood up, I walked over there and got my medal."
Moss returned home to his family and the new baby daughter, Ariana, he thought he would never meet. Despite the aches and pains, he is grateful for the risks so many soldiers took that day.
"I was given a second chance. And to whom much is given ... much is expected. So a lot is expected of me," Moss said.
The soldiers responsible for saving Pvt. Moss were recognized for their service that day and the Army has not changed its policy regarding unexploded ordnances in soldiers
For Sgt. Brown, there was never a question about taking the gamble.
"He was American, he was a solider, he was a brother and he was one of us. And there was nothing gonna stop us from doing what we knew what we had to do … We knew we did right. In that screwed up world we did something right," Brown said.
Watch the full story on "20/20" Friday at 10 p.m. ET.