As a best practice, you really want to move this activity out of the constructor and into onRegister. First, in MultiCore, it wouldn't work. You don't get your facade reference until initializeNotifier which comes after construction and before onRegister.
But more practically, anytime a mediators or proxy interacts with other actors via the facade, they should already be registered and able to take part in any conversations they start. For a Proxy, this means being retrievable, for mediators it means being retrievable and ready to receive notifications.