531. On receiving one or several petitions, the labour commissioner general,(1) if he concludes that the petitioning association is the only association that was certified in the territory of the new school board or is the only association that has filed a petition, shall certify it, indicating which group of employees forms the bargaining unit;
(2) if he concludes that the petitioning association has obtained the agreement of all the associations of employees qualified for certification to represent a group of employees, shall certify it, indicating which group of employees forms the bargaining unit;
(3) if he concludes that the petitioning associations agree to certification of one of their number to represent a group of employees, shall certify it, indicating which group of employees forms the bargaining unit;
(4) if he concludes that the petitioning associations do not agree to certification of one of their number to represent a group of employees, shall order a vote by secret ballot.