@ TabooFantasy - If their 'service' is providing a team, then they are allowed to choose either the "Business and Services" MarketPlace Forum, or the "TeamWork" Forum. Just like an FC that hunts, penguins, evil trees or shooting stars, may choose to use either the "Minigames and D&Ds" Forum or the "Recruitment – Specialist, Questing & Minigames" Forum.
As long as they as not advertising in both, and the forum they have chosen to use is relevant, it's fine.