Is there a way to get an identifier from a physical keyboard?

Question

I need to identify some hardware keyboards connected via bluetooth to my app.

I have it connected via bluetooth and I can access to it via GCKeyboard.coalesced; I know that it comes from class GCKeyboard that implements GCDevice and I cannot get an unique identifier of the device currently connected: I only can get the vendorName and product category that only returns "Keyboard".

I also tried to get the bluetooth device but that keyboard is not BLE and neither is MFi compliant.

Is there a turnaround that I could do?