Do they need to know what FMLA and ADA are? Yes. Do they need to know how to administer all the details? No. If you spend too much time teaching them about the boring details of disability and leave of absence management you're going to lose your audience.
FMLA Myth #5: You cannot contact an employee about work during their FMLA leave. Reality: You cannot ask an employee to perform work while they are on a leave but you can reach out to ask basic questions.