What to do with a company when it's been discovered they misclassified employees as Exempt status when, in fact the employees are Non-Exempt? If a lawsuit is filed to recover overtime wages that were not paid, can the employer retaliate against

What to do with a company when it's been discovered they misclassified employees as Exempt status when, in fact the employees are Non-Exempt? If a lawsuit is filed to recover overtime wages that were not paid, can the employer retaliate against the employees that become involved or is there any laws in place to protect these employees?