"Because a union’s other duties include the duty to see to it that an employer meets its [collective bargaining agreement] obligations, the employer’s duty to furnish information extends to data requested in order properly to administer and police a collective bargaining agreement." N.Y. & Presbyterian Hosp. v. NLRB , 649 F.3d 723, 729 (D.C. Cir. 2011) (citation and internal quotation marks omitted)."[T]he duty imposed by section 8(a)(5) is subject to a minimum standard of relevance: ‘The union’s need and the employer’s duty depend, in all cases, on the probability that the desired information [is] relevant, and that it [will] be of use to the union in carrying out its statutory duties and responsibilities.