On 16 January 2020, Maghoma signed an 18-month contract with the B team of Championship club Brentford for an undisclosed fee.[5] In what remained of the 2019–20 season, he made 10 appearances and scored one goal.[6] Maghoma was included in the first team group for the 2020–21pre-season and was an unused substitute on the opening day of the regular season.[7] At the end of an injury hit 2020–21 season, he signed a new one-year contract, with the option of a further year.[7] Maghoma returned fit for the 2021–22 pre-season and with the first team now playing Premier League football,[8] a midfield injury crisis saw him win a number of first team call-ups between October and December 2021.[9][10] On 10 January 2022, it was announced that he had signed a new 3+1⁄2-year contract.[11] Maghoma was a part of the B team's 2021–22 London Senior Cup-winning squad and was promoted into the first team squad at the end of the campaign.[12]
In July 2022, Maghoma joined League Two club AFC Wimbledon on loan for the duration of the 2022–23 season.[13] He made the first competitive appearance of his career on the opening day of the season, with a start in a 2–0 victory over Gillingham.[14] Following 24 appearances,[14] Maghoma was sidelined by an ankle injury suffered in training in mid-December,[15] which led to his recall from the loan on 5 January 2023.[16] 18 days later, he joined League One club Milton Keynes Dons on loan until the end of the 2022–23 season.[17][18]