Apple requires you set the Bluetooth protocol name. I cannot seem to find information on how to set it or even figure out what the default reverse-DNS string is.
We are using a Raspberry Pi 3 CanaKit.
This is from apple:
As part of your communication with the accessory manufacturer, you must find out what protocols a given accessory supports. To prevent namespace conflicts, protocol names are specified as reverse-DNS strings of the form com.apple.myProtocol. This allows each manufacturer to define as many protocols as needed to support their line of accessories.