Bowlan started 2019 with the Single–A Lexington Legends and was promoted to the High–A Wilmington Blue Rocks during the season.[3] Pitching for Wilmington in July, he threw a no-hitter against the Carolina Mudcats.[4] Over 26 games (23 starts) between the two teams, Bowlan went 11–5 with a 3.14 ERA and 150 strikeouts over 146 innings.[5] He did not play a game in 2020 due to the cancellation of the minor league season because of the COVID-19 pandemic.[6] In 2021, Bowlan appeared in only four games in prior to undergoing Tommy John surgery in May.[7]
Bowlan was optioned to Double-A Northwest Arkansas to begin the 2023 season.[10] In 24 games (21 starts) split between Northwest Arkansas and the Triple–A Omaha Storm Chasers, he registered a cumulative 7–11 record and 5.91 ERA with 105 strikeouts in 102.0 innings of work. On September 19, 2023, Bowlan was promoted to the major leagues for the first time.[11] He appeared in two games for the Royals, pitching three innings and registering a 3.00 ERA.
Bowlan was optioned to Triple–A Omaha to begin the 2024 season.[12]