Thomas joined the Broncos late in training camp following the loss of Jamal Carter to injured reserve and was released at the start of September when the team trimmed its roster to 53.
As well as providing cover on defense, he could be a useful contributor on special teams.
McKenzie, the Broncos’ sixth-round pick in 2017, notably struggled to hold on to the ball last season and was also waived during roster cutdowns at the start of September despite an electric punt return in preseason.
He cleared waivers and was signed to the practice squad before being added to the active roster when safety Su’a Cravens was moved to injured reserve last week.
But McKenzie was inactive Sunday with veteran cornerback Adam Jones — signed as a free agent during the preseason — fielding punts in the week one win against Seattle.
Henderson has endured a troubled start to his NFL career. The 2017 third-round pick suffered a thumb injury during preseason and missed the rest of the season, and was arrested for marijuana possession in January.
He failed to report to training camp in July as he dealt with personal issues and was suspended one game by the league.