WMATA Flexible Funding and Safety Improvement Act This bill amends federal transportation law to authorize the Department of Transportation to make grants to finance the operating cost of equipment and facilities for use in an urbanized area with a population of at least 200,000 for a public transportation system that: (1) operates as an interstate compact agency; and (2) is an agency and instrumentality of three signatories that have enacted legislation to provide a dedicated source of revenue to finance the operating costs of equipment and facilities for use in public transportation and that results in the collection of local and state funds covering at least 50% of such costs. The consent of Congress is granted for Maryland, Virginia, and the District of Columbia to amend the Washington Metropolitan Area Transit Regulation Compact to authorize the Washington Metropolitan Area Transit Authority (WMATA) to establish and maintain the Jeanice McMillan WMATA Track Safety Task Force and the Thomasine Maria Smith WMATA Bus Safety Task Force. The compact may be amended to: (1) direct the Inspector General for the transit authority, prior to the renewal of any private MetroAccess contract by such authority for the provision of demand response services, to conduct a review of the MetroAccess program; and (2) prohibit the authority from renewing the MetroAccess contract unless specified conditions are met. "MetroAcess" is the paratransit service of WMATA for individuals whose disability prevents them from using a bus or rail facility. The compact may be amended to provide for a flat fare, free transfer pilot program, and an ability-based fares program.