In Round 10 2019, Cust made his NRL debut for Manly Warringah against the Cronulla-Sutherland Sharks at Shark Park. Cust scored his first try for Manly in Round 12 2019 against Penrith at Penrith Park in which Manly lost the match 15-12.[4][5]
Cust was limited to only ten games for Manly in the 2021 NRL season. He did not play in the club's finals campaign which saw Manly reach the preliminary final.[6]
Wigan
On 12 November 2021, Cust signed a two-year deal with English side Wigan.[7]
In round 1 of the 2022 Super League season, Cust made his club debut for Wigan in a 24-10 victory over Hull Kingston Rovers.[8]
On 28 May 2022, he played for Wigan in their 2022 Challenge Cup Final victory over Huddersfield.[9]
In round 24 of the 2022 Super League season, Cust scored two tries in a 52-6 victory over Toulouse Olympique.[10]
Cust played 14 games for Wigan in the 2023 Super League season. Cust did not play in Wigan's 2023 Super League Grand Final victory over the Catalans Dragons.[11]
Salford Red Devils
On 24 October 2023 it was reported that he had signed for Salford Red Devils for 2024[12]
Hull F.C.
On 11 October 2024, it was reported that he had signed for Hull F.C. on a two-year deal.[13]