Note that in Mbed OS 5.8 we will add a native LoRaWAN stack which will work with both SX1272 and SX1276 radios. Thread-safe, will work with any Mbed board, and EU pre-certified. Thus will also work with nRF5x boards, and should play nicely along with Bluetooth (although that poses some challenges on how to properly do deep sleep with both radios, but OK).
Demonstration application is here: mbed-os-example-lora.
Feature branch for Mbed OS is here and will be mainlined in the next major release.