The correct answer is:
Since neither opponent saw or felt the ball touch the hair, the opponents get the point.
From The Code, Item 19:
While a ball grazing the hair of a player would be grounds for the player losing the point, according to Item 19, it is the player who shall concede the point when it happens, and the opponent is not entitled to make the call. Since neither of Vanessa’s opponents believe the ball grazed one of the player’s hair, they get to keep the point.
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