Usually they are not authorized to contact you personally. All the communication comes from IRCC directly. In Canada medical panel don't usually tell you why a medical furtherance let apart normal medical procedures. Sounds weird to me, make sure you double check with people around or someone who had experience with same medical panel. Also if possible notify IRCC if you can and make sure the panel knows that you are going to do this ( reporting this to IRCC). Also you can research the pulmonologist being referred is IRCC approved, if not confront this medical panel.