You must have a doctor somewhere in your network 1 degree of separation away. Get a friend to ask for a favor to invite the doctor to a meal at a nice place, your treat. Be up front about your intent. At the right time, pitch to the doctor the idea of interacting on the job with doctor and/or staff. And don't promise the doctor any equity. Maybe free access to the product.
Doctors have to be very careful with this type of request. If they allow an unrelated third-party to view protected health information, even inadvertently, then they could be punished for a HIPAA violation. Most well-managed healthcare provider organizations would outright prohibit this unless there is a business associate agreement in place.