I believe what is being referred to is, (in UE5 anyway), in "UE5\Engine\Plugins\FX\Niagara\Source\Niagara\Private\NiagaraDataInterfaceAudioPlayer.cpp" you'll find references to the following functionality within Niagara:-
PlayOneShotAudio
PlayPersistentAudio
SetParameterBool
SetParameterInteger
SetParameterFloat
UpdateVolume
UpdatePitch
UpdateLocation
UpdateRotation
SetPausedState
It would be great if there was a way to override the internal functions by binding something more Wwise friendly into the system....
Ollie