How to use Arduino as BLE client with MBed library?

I am creating a device that will act as a BLE hub. It acts as both a peripheral and a central device at the same time.

I have attempted to use the standard arduinoBLE library for this and although I have managed to get everything working, pairing isn't supported.

The Mbed BLE library does support pairing and I have a great library that I am using for the peripheral part.

The problem I am having is getting it to work as a central device.
I am unable to get the example GATT "client" code to work because the examples fail to compile with the following error:

ble/common/FunctionPointerWithContext.h: No such file or directory

When I look at the Mbed documentation, the first version this file is mentioned is with 5.13...
So I can only assume that the Mbed BLE version on Arduino is before this.

Does anyone know how to get an Mbed Gatt Client working an Arduino? I can't find any examples and can't seem to work it out.

I have a Nano 33 BLE sense as well as a Nano 33 IOT.

I have since discovered that the file does exist within the ble library, however it isn't in /common but directly in /ble. However, when I import this class I end up with many errors.