Yes you can!
Add your gym to btwb here. The same way official affiliates do. You'll get a free 30 day trail. After that you'll be billed automatically for a btwb gym subscription based on the number of members in your gym.
Subscription options for all gyms are as follows:
Members Pay: each individual member of the gym must pay for their own subscription ($7.99 per month or $87 per year)
The benefit to a btwb Gym Subscription is that gyms get to offer an additional service to their members free of charge.