Arndt came in relief of starting Jennings in the second half of the team's Week 15 loss to the BC Lions.

[5] Arndt started the following match against the division leading Ti-Cats but was unable to effectively move the ball down the field, completing 17 of 30 pass attempts for only 112 yards with no touchdowns or interceptions.

[11] Arndt retired following his release by the BC Lions, and joined the Edmonton Elks as an offensive assistant on September 1, 2021.

[13] Following the season, in December 2022, Arndt announced that he was stepping down from his role as quarterbacks coach in order to pursue a playing opportunity.

[14] Arndt portrayed Penn State play-caller Matt McGloin in the HBO movie Paterno, which was released in early April 2018.