I take it the github project is some offshoot of reticulum and not the official project?

I didn't see that feature in the mobile app and the only tranport layers I see in the documentation is LoRa and IP networks.

https://reticulum.network/manual/networks.html

I'd expect if they could use Meshtastic, they would be very quick to mention that since the Meshtastic network is already so strong.