If the commissioner fails to bring suit within ten days to restrain a violation as provided in Subsection C of R.S. 30:542 any person in interest adversely affected by the violation who has notified the commissioner in writing of the violation or threat thereof and has requested the commissioner to sue, may bring suit to prevent any or further violations, in the district court of any parish in which the commissioner could have brought suit. If the court holds that injunctive relief should be granted, the commissioner shall be made a party and shall be substituted for the person who brought the suit and the injunction shall be issued as if the commissioner had at all times been the complaining party.
La. R.S. § 30:543