[6] He spent 2017 with the Cedar Rapids Kernels, going 5–3 with a 3.11 ERA in 14 starts, and began 2018 with the Fort Myers Miracle where he was named a Florida State League All-Star before being promoted to the Chattanooga Lookouts in July, where he finished the season.

[11] Wells began 2019 with the Pensacola Blue Wahoos,[12] but underwent Tommy John surgery in May, forcing him to miss the remainder of the season.

[17] On June 2, Wells earned his first career major league victory, pitching three scoreless innings giving up only one hit against the Minnesota Twins.

[19] Wells missed time during the season due to wrist and shoulder injuries, but still pitched 57 innings in relief in which he went 2-3 with a 4.11 ERA and 65 strikeouts.

Wells began the season in the Orioles bullpen, where he pitched five shutout innings in a winning effort against the Texas Rangers after an injury to starter Kyle Bradish.

Wells made three scoreless relief appearances, including earning his fifth career save in a 2-0 win over the Red Sox on September 28 that clinched the Orioles' first AL East title since 2014 and secured the franchise's first 100-win season since 1980.