I do not teach Bodyshred (and I’m personally not a big fan of Jillian Michaels style), but I’ve taught my own version of an interval/weights program for over 10 years now and it does very well. The format itself is very effective for calorie burning and weight loss. One thing to make sure of (and I’m hoping this was included in your certification training) is that you show modifications for the more advanced, higher impact moves. One size does not fit all when it comes to these programs and they can be intimidating, which is one thing that could be holding some people back. You want to make sure all of your participants feel successful in your class.
Keep marketing the program as you wish, and ultimately people will come to class because of you and your instruction, not necessarily the name. However, if it doesn’t take off eventually, it doesn’t mean it’s not a good program.