Laird RG191 working in Australia

I don’t have the 915Mhz version to test this, but pretty sure you can choose “download current configuration as JSON” under LoRa -> Advanced which give you a file very similar to the the one TTN provides:

change the one from the gateway to match the frequencies listed on the TTN one then upload the changed JSON file back using the “upload a custom configuration JSON file”.

Underneath it’s just running the normal Semtech packet forwarder so I can’t imagine this wouldn’t work. You might even be able to just upload the TTN file over without any changes.