The plan of operation of a corporation shall set forth specifically or by reference to another document, which shall be appended thereto, the provisions for job security for employees at regional race tracks made and accepted by the employer and the employees involved individually or through their collective bargaining representatives. Such agreements shall cover race tracks affected by off-track betting conducted by the regional corporation, as prescribed by law, and the different classifications of track employees there employed; provided, however, for the purposes of this section, the New York City, Suffolk, Nassau, mid-Hudson and Catskill regions shall constitute a single combined region, and all job security agreements for corporations in this single combined region relating to tracks and their employees located within such single combined region shall be jointly negotiated by the regional corporations existing at the time of such negotiations, and each regional corporation thereafter created within such single combined region shall, at the time of its creation, be deemed a party to previously negotiated existing agreements by other regional corporations and employees in such single combined region, and such existing agreements shall be deemed a part of its proposed plan of operation. All such provisions for job security as concern track employees shall be approved by the commission and when approved shall be deemed a part of the plan of operation of the corporation.