Matumona landed at FC Brussels in 2007 for a sum of €60,000.
Matumona walked out of FC Brussels on 2 November 2007 after he accused club chairman Johan Vermeersch of making racist remarks towards him during a crisis meeting at the struggling club. Vermeersch was reported to have told Matumona to "think about other things than trees and bananas". The incident also prompted the club's main sponsor, Korean car manufacturer Kia, to withdraw their sponsorship of the Belgian side. But he terminated his contract unilaterally with the club following the racist remarks against him by the President. According to the player's lawyer, Johan Vermeersch had rebuked Matumona and had explained that he "was not in his country and had to forget trees and bananas" in the presence of staff and other players. The lawyer confirms his statements but said it was "a joke". Although on 7 November Matumona agreed to return to FC Brussels after talks with Vermeesch, Kia still refused to renew their contract with the club.