It’s not open source if that’s what you mean. If you think that stops people looking at code then I’ll have some of what you’re smoking please.
If you’re genuinely interested in how the Find My system works Here’s a good paper on it. The papers publishers even have an open source tool to connect to Apples Find My network which is neat.
We discovered the bongo technique about two years ago, I genuinely can’t remember how we gave her attention before that, for now there is only bongos.