Integrate third party lora device with LM lora controller

[admin]

Correct, this way you don't even need LM to be on the same network as the gateway. Both must have Internet access and that's it.
There's an alternative gateway for a similar price: https://www.antratek.com/indoor-femto-lorawan-gateway
They state that it has a built-in server that can be interfaced via MQTT so The Things Network is not needed. Dragino has a similar feature but I was not able to make it work.