As a true freshman at Rutgers in 2016, Maddox-Williams appeared in 11 games, six as a starter, and was named to ESPN's Freshman All-Big Ten Conference team after recording 47 tackles.[4] He suffered a torn ACL prior to the 2017 season and thus missed it in its entirety.[5] He returned in 2018 and started all 12 games while posting 48 tackles.[3]
In 2019, Maddox-Williams served as team captain and played 12 games, eight as a starter, while tallying 45 tackles, 5.5 tackles-for-loss and 1.5 sacks.[2][3] He played in nine games, one as a starter, in the 2020 season, having 39 tackles along with three pass breakups.[2] In his final year, the 2021 season, he posted 27 tackles, two pass breakups and a fumble recovery while appearing in eight games.[6] Off the field, Maddox-Williams was a five-time Academic All-Big Ten selection.[2] He was invited to the NFLPA Collegiate Bowl at the conclusion of his Rutgers career.[2]
Maddox-Williams was signed by the Philadelphia Eagles on August 19, 2023.[13] In his only preseason appearance, he recorded seven tackles, two pass breakups, a tackle for loss, and had an interception, which he returned 42 yards against the Indianapolis Colts.[14][15] He was released by the team at the final roster cuts.[16]
Arizona Cardinals
On September 13, 2023, Maddox-Williams was signed by the Arizona Cardinals to their practice squad.[17] He was promoted to the active roster on December 20.[18] He finished the season having appeared in three games.[1]
On August 27, 2024, Maddox-Williams was waived by the Cardinals.[19]