Thank you kindly, fellow alliteration admirer! You may have more reasons to enjoy the dungeon boss when you encounter it!
As for the navigational design, we started with a completely blank slate and just asked ourselves "how would we design a Zelda-like game from the ground up specifically for blind gamers?" Everything I prototyped, I would make sure that I tested with my eyes closed until it actually felt useful and natural. Given that we're aiming for a Zelda-like fantasy world, it was convenient to put all of this functionality into a named magic item and teach players how to use it, the same as we would teach them how to fire a bow or swing a sword. Then, I gave an early prototype to testers in the Discord server, and kept iterating on all of the functionality based on their feedback for most of the jam. We had blind testers, sighted testers, and proper accessibility consultants. They had plenty of stellar feedback and ideas from the very start, and we were still tweaking and adding features to the Divining Rod right up to the jam deadline. We are still continuing to receive more fantastic ideas for how to make it even better every day! We hope to keep polishing it, and figure out how to make it reusable for other games targeting blind accessibility.
That said, I do think the Divining Rod Lock-On system largely resembles Z-targeting from Ocarina of Time, or the Metroid Prime lock-on system, but both of those were only meant for targeting enemies, not for general navigation. I don't think I've ever seen a game handle sonar quite like this, but it wouldn't surprise me if we weren't the first. I especially have never seen a combination like sonar + lock-on for navigation, but let me know if you ever find any prior art!
If anyone else wants to borrow the Divining Rod mechanics in order to make their own games more accessible, please do! It would always be nice to get a shout-out credit for the inspiration, but that's just an optional "nice to have." The real goal here is to help enable as many games as possible become more accessible!