Every day for almost 15 years, Col. Rob Maness wondered about the badly-burned man he’d tried to keep conscious on a gurney after terrorists flew a 757 airliner into the Pentagon on Sept. 11, 2001.

Did he make it? Was he still alive? Was he able to fully recover and live a happy and fulfilling life?

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“It’s something I’ve always thought about, but I never had an answer,” Maness, 54, now living in Madisonville, Louisiana, and running for the U.S. Senate as a Republican, tells PEOPLE. “It was always a mystery.”

Until now.

Last week, while attending the Republican National Convention in Cleveland, Maness, now retired from the Air Force, was told that former Texas governor Rick Perry wanted to meet with him and several other veterans.

After shaking Maness’ hand, Gov. Perry told him, “Rob, I want you to meet somebody. He was in the Pentagon on 9/11, too.”

The governor introduced him to Brian Birdwell, a state senator from Granbury, Texas, who had been severely burned on the right side of his body in the attack and required 39 surgeries.

As Birdwell, 54, relayed his story and mentioned that a stranger had helped hold his IV line and talked to him while he was waiting to be transported to a hospital, Maness knew: This was the man he had thought about daily since that horrific morning when American Airlines Flight 77 crashed into the Pentagon.

“When I realized that I was looking at the same gentleman, I started to cry and told him I was so grateful that he was still alive,” Maness tells PEOPLE. “We hugged each other and neither of us could believe that we were talking again. What are the odds?”

Birdwell, then working as an Army lieutenant colonel, was returning from the men’s room to his desk in the E Ring at the Pentagon at 9:37 a.m. on Sept. 11, when he heard a loud roaring sound that he thought was a bomb.

“A nanosecond later, I was tossed through the air like a rag doll just 15 or 20 feet away from where the nose of the 757 hit the building,” he tells PEOPLE. “I thought for sure that I would die.”

His clothes burned away and his name tag melted, Birdwell was rescued by four men and taken outside to a makeshift triage area, where a doctor gave him a shot of morphine and put an IV in one of his feet because his leather shoes had protected the skin there.

Col. Rob Maness, who was one of the last people to escape the building, had just helped an injured Navy petty officer walk to the emergency treatment area when a chaplain called him over to help Birdwell.

“He was in really bad shape – it didn’t look like he was going to make it,” Maness tells PEOPLE. “I was told to stand there and hold his IV because it was leaking. He was in such tremendous pain and was ready to pass out, so I kept talking to him, trying to comfort him and keep him awake. After I watched them take him away to a hospital, I couldn’t stop thinking about him. He was the last survivor I saw that day.”

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Birdwell’s burns were so severe, doctors gave him less than a one percent chance of survival. At one point, he even said his farewells to his wife, Mel, and their son, Matt, then 12. Little by little, though, during 92 days of treatments and surgeries at Washington Hospital Center, he started to improve.

“I owe the fact that I’m here today to all of the people like Rob Maness who played a supporting role in helping me that day,” he says. “I didn’t survive an 80-ton, 757 coming through the hall at 530 miles an hour because the Army made me a tough guy. The Lord had something else in mind for me. That’s why I survived.”

Now that he and Maness have been reunited, they plan to stay in touch, so that another 15 years doesn’t slip away.

“The shining moment of my convention experience was meeting Brian and seeing that he is now healed, happy and enjoying life with his family,” Maness says. “I’m so grateful that I could play small a part in getting him there.”

As for Birdwell, he says he’s found a new friend for life.