Is it still worth using LoRaWAN protocol in a scenario where I have several LoRa devices but no gateway?

My project idea is low-cost GPS transponders for use in a music festival/burning man style scenario: users would clip a transponder onto their bag, the devices would get their GPS reading, share this with each other via LoRa then report the data to users’ phones over bluetooth, so you have a map of where your friends are inside the event. This scenario is built assuming 3G/LTE connectivity is spotty or nonexistent & no permanent IoT gateway out to the proper internet would be needed (or feasible).

Is it still worth it to use LoRaWAN or should I strike out on my own protocol-wise? I assume a DIY approach means I’d need my own solution for device identification & encryption, but if the existing tools/libraries are all built assuming an node<->gateway model it might not be worth the fight.