I also got missing symbols in the Windowed (Last 5 seconds) recording mode in Xcode 15.3 with an iPhone 14 pro (iOS 16.7.2).
Everything works fine with the Deferred recording mode (File > Recording Options... > Recording Mode, in Global Options at the bottom).
The same project works fine with both recording modes in Xcode 14.
Also confirmed this behaviour with a project created from the unmodified "Game" Xcode template.