The NFL and the players association agreed last week to an opt-out clause for the upcoming season. Those who choose to voluntarily sit out will receive a $150,000 stipend and those with medical opt outs will receive $350,000 rather than their contractual salary.
Elway said Peko notified the Broncos "it was more dangerous for him" to play during the pandemic.
It's uncertain whether Peko has a medical condition himself that imperiled his health or if his decision to skip the season was related to his wife's recent bout with cancer.
A year ago, Peko left the Buffalo Bills training camp to be with his wife, Giuliana, who was battling Hodgkin's Lymphoma. The couple later said she was cancer free.
Peko, 27, spent parts of the 2016 and 2017 seasons in Denver, which signed him as an undrafted free agent out of Oregon State. He was in his second stint with the Broncos this year after playing with the Bills and Colts in 2018 and '19.
The Broncos are down to 81 players and it's possible another player will opt out, Elway said.
"There's been some rumblings about a couple of guys, but we've not heard anything else yet," Elway said.