The two men struggled, and Moogalian was shot in the neck. The French-American collapsed to the floor, bleeding heavily.
He made eye contact with his wife.
"C'est fini," Moogalian told her. "It's over."
"I really thought he was going to die," said his wife, Isabelle Risacher Moogalian.
She told CNN her husband played dead to avoid getting shot again.
Mark Moogalian was one of five passengers on the Amsterdam-to-Paris train who tried to disarm the gunman, who wielded enough weaponry to kill everyone on board.
A French prosecutor said the suspect, Ayoub El Khazzani
, had an AKM assault rifle with 270 rounds of ammunition, a Luger M80 pistol with a full magazine, a box cutter and a water-bottle-sized container full of gasoline.
"I thought to myself, everyone on this train is going to die," Risacher Moogalian said.
But no one died, thanks to four other men who helped subdue the assailant Friday.
Moogalian is recovering at a hospital in France and could be released from the emergency room Wednesday, his wife said.
Once he's recovered, he will be rewarded with the Legion of Honor, France's highest recognition.
The four other men who helped bring down the gunman have already received the Legion of Honor: Briton Chris Norman
and Americans Anthony Sadler, Spencer Stone and Alek Skarlatos
And the awards keep coming.
Skarlatos to get U.S. Army medal
Skarlatos, a specialist with the Oregon National Guard, will receive the Soldier's Medal, the U.S. Army's highest award for acts of heroism not involving actual conflict with an enemy.
The 22-year-old "forcefully wrestled the two firearms from the gunman's possession," the Army said. "As the gunman fought relentlessly, wielding a box-cutting razor, SPC Skarlatos seized the assailant's own rifle to employ as a blunt weapon."
Skarlatos, on a monthlong break after serving in Afghanistan, was on vacation with his longtime friends Sadler and Stone when the trio became international heroes.
Stone nominated for another medal
Stone, a U.S. Air Force serviceman, has been nominated for the Airman's Medal, the Air Force equivalent of the Army's Soldier's Medal.
After Moogalian was shot, Stone rushed the gunman, getting slashed several times with a box cutter in the process. He almost had his thumb cut off.
Even with his injuries, the Airman first class tended to Moogalian and his gunshot wound, Risacher Moogalian told CNN.
"My husband was lying on the floor," she said. "Spencer was next to him, and he was bleeding, too."
She said Stone put his finger on her husband's wound and spoke to him: 'Hey man, so tell me where you're from. So you are from Virginia? I'm from California. Everything will be OK.' "
Risacher Moogalian said she believes her husband would be dead if not for Stone's help.
"Yes, I'm sure because he lost a tremendous amount of blood, and it saved his life."
Stone's commander: 'They are heroes'
On Wednesday, Stone's Air Force commander told reporters that the airman first class will be able to return to full duty in the coming months, despite the severity of his injuries.
"His wounds are healing. He's in good spirits," Lt. Col. Richard Smith said at Ramstein Air Base in Germany, where Stone is receiving medical care.
In a statement read by Smith, Stone said he believed others would have done what he did to help to subdue the gunman last Friday.
"It seemed the only option I had. I do know that the extensive Air Force medical training I received allowed me to provide first aid to a fellow passenger and potentially save his life, and for that I am grateful," Stone's statement read.
But Smith said Stone and others on the train were heroes.
"There are a lot of men and women who got off that train last Friday and went home to their friends and families because of the actions they took. They are heroes. Plain and simple," said Smith, who is visiting Stone at Ramstein.
Prosecutor: Gunman had terrorist intent
French prosecutor Francois Molins said El Khazzani
, the suspected gunman, carried hundreds of rounds of ammunition with him.
Before he assembled his weapon in a restroom between two train cars, El Khazzani sat on the train listening to a YouTube file of "an individual calling his followers to combat and urging them to take up arms in the name of the Prophet," Molins said, saying this was indication of his terrorist intent.
A judicial investigation has been opened, Molins said.
The 25-year-old Moroccan has been indicted on charges of attempted murder and membership in a terrorist organization, the prosecutor said, because the gunman allegedly wanted to kill all the passengers on the train.
The indictment also includes a charge of possession and carrying of weapons. All the charges are under French terrorism law.
But the suspect's lawyer told CNN affiliate BFMTV that her client denies he was trying to launch a terror attack. Instead, attorney Sophie David said, he boarded the train with the intention of robbing passengers.
David has since said she no longer wants to speak to the media and has not returned CNN's calls.
Molins said El Khazzani has invoked his right to remain silent after days of "evasive answers."