[colanderman]

I know only basics about mesh networks per se. I'm speaking here from a background in signal theory / amateur radio / research on the LoRa protocol. If you have specific questions on those aspects feel free to contact me, my e-mail is in my profile.

Is your goal nondetection? If so, know that triangulating a radio signal is fairly straightforward, even in a dragnet fashion. The exception I think is something like cryptographic DSSS (found in military use) wherein not only is the signal far below the noise floor, but the spreading function is not predictable by an adversary (LoRa being very much predictable). Even then, you're limited by physics to only be able to transmit so far without the signal being detectable near the transmitter.