Koenig also played for the Birmingham Bloomfield Beavers of the United Shore Professional Baseball League during the 2017 season.

[2] Koenig returned to San Rafael in 2018 and was named the Pacific Association Pitcher of the Year after posting a 11–1 record with 3.54 ERA and 140 strikeouts in 16 starts.

Koenig trained with his younger brother, a player at Cabrillo College, until taking part in Oakland's fall instructional league.

[10] Koenig’s third career start for the Oakland Athletics came on June 19, vs the Kansas City Royals where he would pitch 5 ⅔ innings of scoreless ball, earning him his first MLB win.

[11] Koenig finished his rookie campaign appearing in 10 games (5 starts), pitching to a 1-3 record and 5.72 ERA with 22 strikeouts in 39.1 innings of work.

On February 23, 2023, Koenig signed a minor league contract with the San Diego Padres organization.

[12] In 48 appearances split between the Double-A San Antonio Missions and Triple-A El Paso Chihuahuas, he pitched to a cumulative 3.81 ERA with 70 strikeouts and 7 saves in 59 innings of work.