I have a client who trains with other trainers on the weekends. How do I ensure she is getting a well rounded program?

I work in a corporate fitness facility that is only open M-F and I am not allowed to train outdoors on weekends due to liability reasons. My client is very aggressive with her weight loss goals, and after a few months with me she decided to add a "bonus trainer" to meet with her on Saturdays. How in the world do I make sure she is getting a well rounded program and plan our workouts properly? This other trainer has an expired cert and is having her do things I don't agree with. Help!