My guess is something like Dragon Fly Cobalt should do the trick. On a side note, it's highly unlikely that you will notice any meaningful difference between 24/48 (Airplay2) and Hi-Res (24/96).Yes. AirPlay unfortunately does does not support hi-res, and Apple explicitly states hi-res playback needs a wired connection.
In the screenshot, Apple documentation does not say how on how to wire the iPhone to an external DaC.About lossless audio in Apple Music - Apple Support
Learn about lossless audio in Apple Music and how to turn it on or off for your device.support.apple.com