Different movement's often have several different legitimate applications. Different people look for different things in the forms. Over time people develop their own way of seeing and understanding the forms. This shapes the way that they practice them. Memories are fallible. Over the years people stop practicing the form as they were taught it and begin to practice it as they Understand it. But understanding changes over time and hence so do the forms. If you like the class, like the instructor, like what you are leaning and like practicing it, I would not worry about the credentials of the instructor or the "legitimacy" of the instructor or of what they teach. As you begin to practice you will become more familiar with the art. You will be able to see the similarities and differences in the way it is practiced for yourself. If you begin to feel its not for you any more then change. But as long as you and your wife can fit practice in with daily life, and as long as you are enjoying and learning from the experience - why worry?