The announcement of the government inquiry and the resignation last week of Andre Markgraaff, the Springbok coach taped calling black rugby officials "f---ing kaffirs", has made Mr van Rooyen, a long-time thorn in the side of the white rugby establishment, even bolder. Even in the heady days of World Cup victory in 1995, he now reveals, when the new South Africa made its triumphant return to the international stage, black officials were convinced unification of black and white rugby was a sham.
The formation of a new governing body for rugby in 1992 had been accompanied by pledges of black development programmes and shared power. The white game, for so long an outlet for Afrikaner nationalism and racism, was to relinquish some power and let blacks in. But Mr van Rooyen, 35, a "coloured" (mixed-race) official with a Johannesburg township team, says unification has left the black game in ruins, annihilated by white officials sure of their racial superiority and hell-bent on retaining power.
Black clubs, always poorer than white, have been allowed to die for lack of funds. Township teams have merged with nearby white clubs, only to be flattened by the more powerful partner. "Only two of the 13 clubs that formed the black Transvaal union still exist," says Mr van Rooyen, and their players have nowhere to go. Although teams are now in one union, they remain segregated. "You can count on one hand the number of black men playing for white clubs, and vice versa," says Mr van Rooyen.
The official feels betrayed. "We legitimised white rugby. We got it back into international competition. We got them the World Cup. They claim to have spent 17m rand (pounds 2.3m) on development in Transvaal, but I can't see where. Not one black player has emerged." Last week Peter Jooste, the last man to captain a separate black South African national side, suggested black clubs should withdraw from the amalgamated South African Rugby Football Union (Sarfu) if they wanted to survive, but Mr van Rooyen continues to fight from within.
His tenacity has brought him into confrontation with Sarfu's president, Louis Luyt, the macho, bullying Afrikaner millionaire, who has dominated South African rugby for almost two decades. As head of the sport both at national level and in Transvaal, one of the most powerful regions, Mr Luyt's grip is absolute. His son-in-law is chief executive of Sarfu, and the sport's upper echelons are stuffed with his yes-men. Those who oppose him are no longer around.
Four months ago Mr van Rooyen, who had become Mr Luyt's deputy in Transvaal, decided to challenge him for the top job in the province. Complaining that the white official never let him see a player's contract or a sponsorship deal, he received promises of support from more than half the clubs.
But the big day ended in humiliation for Mr van Rooyen. Instead of a secret vote, Mr Luyt engineered a show of hands, and the challenger watched his promised support wither away. The rugby boss was characteristically gracious in victory, telling Mr van Rooyen, who triumphed over poverty and apartheid to head a management consultancy, that he was too stupid to be a rugby official.
"You're gone now," he taunted. "Thank God you're gone."
Now Mr van Rooyen is having his revenge. Over the past four months he has been gathering information to persuade the government to launch an inquiry into how South African rugby is being run.
When Steve Tshwete, the sports minister, agreed last week, Mr Luyt said he would not co-operate. The white rugby establishment has been forced on the defensive, however, after its racism was exposed on tape, and Mr Luyt subsequently backed down.
Now Mr van Rooyen wants some answers. After unification the big white rugby stadiumsbecame trusts, and no longer had to reveal their beneficiaries; he wants to know where their money is going. Also under scrutiny, he hopes, will be Sarfu sponsorship and business deals, including the tri-nation tournament between South Africa, New Zealand and Australia. Rupert Murdoch is said to have paid $550m (pounds 344m) for TV rights. But Mr van Rooyen says Mr Luyt will not share the details with Sarfu officials: "He told me it was none of my business."
Mr van Rooyen also wants the International Rugby Board to renew its interest in South African rugby. Just because apartheid has gone, he says, does not mean justice has triumphed.