On December 15, 2016, it was revealed that Wolfgang would be one of sixteen men competing in a two-night tournament to crown the first ever WWE United Kingdom Champion on and January 14 and 15, 2017. Young defeated Tyson T-Bone in the first round, advancing to the quarter finals. In the quarter-finals, he went on to defeat Trent Seven before losing to Seven's tag team partner Tyler Bate in the semi finals.
On the September 13 episode of NXT, Wolfgang faced Pete Dunne for the WWE United Kingdom Championship in a losing effort. After the match, Wolfgang was brutally attacked by The Undisputed Era (Adam Cole, Bobby Fish, and Kyle O'Reilly). This attack ended when Trent Seven and Tyler Bate came out to help Wolfgang. On June 18, 2018, it was announced that Wolfgang would fight Adam Cole on the second night of the UK Championship Tournament, for the NXT North American Championship. He would go on to lose the match.
Wolfgang turned heel on the October 31 edition of NXT UK after a losing match against Mark Andrews, allying himself with brothers Mark and Joe Coffey against Andrews, Flash Morgan Webster, and Travis Banks. On the first December 5 episode of NXT UK, the trio of Wolfgang and the Coffey brothers was officially dubbed Gallus during a segment, calling out British Strong Style as well as the returning Travis Banks.
At NXT Heatwave on August 16, 2022, Gallus made their NXT 2.0 debut, attacking Diamond Mine. On August 23, Gallus made their tag team debut on NXT facing NXT UK Tag Team Champions Brooks Jensen and Josh Briggs, which they would go on to win via countout. At Worlds Collide, Gallus became the second team eliminated from the fatal four-way tag team elimination match for the NXT and NXT UK Tag Team Championship. Gallus would go on to have a rivalry with Briggs and Jensen, with the latter winning a no disqualification tag team match between the teams. Gallus was later suspended in September for attacking officials.
At New Year's Evil on January 10, 2023, Gallus returned from their suspension and won a gauntlet match to become the number one contenders for the NXT Tag Team Championship, which Coffey and Wolfgang won at Vengeance Day the month after. On the March 14 episode of NXT, Gallus retained their titles against Pretty Deadly. At NXT Stand and Deliver, Gallus defeated the Creed Brothers and The Family to retain the tag titles with help from a returning Joe Coffey. Gallus would defend against the Creeds and The Dyad in the following months, including a triple threat on the April 14 episode of NXT and against the Creeds at NXT Battleground. At NXT Gold Rush, Gallus defeated Malik Blade and Edris Enofe. At NXT The Great American Bash, Gallus lost the NXT Tag Team Championships to Tony D'Angelo and Channing "Stacks" Lorenzo, ending their reign at 176 days.
On May 2, 2025, all members of Gallus were released from WWE.