Almost three months to the day since the accident, Mr Stewart recalled his close call with death.
"I hit, and I don't know how, but somehow I didn't get any head trauma.
"One of my climbing partners said I didn't make any sound for about 20-30 seconds. He thought I was dead.
"And then I started moaning because my back hurt."
Fortunately, one of his fellow climbers was a doctor, who helped to stabilise him until emergency services arrived about an hour later. He was conscious throughout.
"It was pretty excruciating in my back and right foot."
Mr Stewart was flown by helicopter to Dunedin Hospital, where he had two operations, including one to insert a plate with 12 screws to repair his shattered right heel.
At first, he worried about getting back to work as a structural engineer at the Five Mile Retail Centre development in Queenstown. "But a day later, I was just thinking about surviving - am I going to walk again?"
Three days after the accident, he learned the spine fracture was stable and he would eventually walk again.
"I actually felt really blessed, because I could have easily died. I could have had really bad head trauma, a complex back fracture.
"And if I had landed half a metre to the left or right, I would have landed on a boulder instead of a grassy slope, and that would have been the end of it. I still can't believe that I survived that fall."
He hopes to return to Queenstown this week and learn to walk again.
Mr Stewart has been mountaineering near his home in Lake Tahoe, Nevada, for the past eight years and began rock climbing last year to develop his climbing skills.
He is passionate about it, but admitted the incident had made him reassess his priorities in life.
"I think it's a selfish lifestyle because it's filling us with what we want - it's a need for adventure. It's easy to forget about family. My parents came out to New Zealand to look after me. To me, that's such a selfless act."
Despite the ordeal, Mr Stewart believes he will eventually return to mountaineering. "Mentally, I'm ready to do it." Otago Daily Times