Fitzgibbon was born in North Sydney, New South Wales, Australia and moved to Newcastle at a young age.

[7][8] On 27 September, he played in the Knights' 2015 New South Wales Cup Grand Final win over the Wyong Roos at Parramatta Stadium.

[19] Fitzgibbon only 10 games for Newcastle in the 2021 NRL season and did not play in the club's elimination finals loss against Parramatta.

[22] In July, Fitzgibbon signed a three-year contract with Super League side Warrington Wolves, starting in 2024.

[24] Fitzgibbon played 14 matches for Warrington in the 2024 Super League season as the club reached the semi-final before losing to Hull Kingston Rovers.