I tried out https://github.com/stechyo/godot-steam-audio this jam it worked pretty well, pretty much drop in replacement for sources and listeners for better spatialization.
Another thing I learned is that making modifications to the engine itself isn't actually that scary. You can just clone the source, add some patches, and build another engine and release template (I had to do this for oblique camera projections with https://github.com/V-Sekai/godot_planar_reflection ) .
That's the sound library I still have on my list of things to check out too. Glad it worked well for you :)
Building from source is so polished with Godot, so much work has gone into making it a good solution. Just need to install the required toolset and it just works (tm). Only Android can be a PITA but thats not something we can do much about.
On the camera thing, check out the work I'm doing here: https://github.com/godotengine/godot/pull/116424
It's not done yet but hopefully that's something that will finally pass the muster.
