It is actually federal law that game shows cannot have pre-determined outcomes, and my research suggests that it also bans the host from influencing the outcome. How then is "Ellen's Game of Games" on NBC not in violation of this law? Ellen can clearly manipulate the game board to favor one contestant over another. One of the most obvious example is during the musical chairs game: she picks when and where the 'chair' will emerge, which clearly allows favoritism towards a specific player.
The law (47 USC §509) states the following:
a. Influencing, prearranging, or predetermining outcome It shall be unlawful for any person, with intent to deceive the listening or viewing public—
- To supply to any contestant in a purportedly bona fide contest of intellectual knowledge or intellectual skill any special and secret assistance whereby the outcome of such contest will be in whole or in part prearranged or predetermined.
- By means of persuasion, bribery, intimidation, or otherwise, to induce or cause any contestant in a purportedly bona fide contest of intellectual knowledge or intellectual skill to refrain in any manner from using or displaying his knowledge or skill in such contest, whereby the outcome thereof will be in whole or in part prearranged or predetermined.
- To engage in any artifice or scheme for the purpose of prearranging or predetermining in whole or in part the outcome of a purportedly bona fide contest of intellectual knowledge, intellectual skill, or chance.
I suspect that that the phrase "with intent to deceive the listening or viewing public" is doing a lot of work there. If the host is openly influencing the outcome, it'd be hard to argue that they're trying to trick the public into thinking that the outcome isn't being influenced.