How can I use 'Crossfade by Distance' with an ambient sound using Capsule shaped attenuation?

I have a river running through the center of my map that the player can cross at any time. I am currently using capsule shaped attenuation running along the length of it to ‘shape’ my sound cue. This works ok but I want to enhance the audio by having a stereo sound playing when the player is further away which fades into a more spatialised mono sound as the player gets closer. I have tried to do this with a ‘Crossfade by distance’ node but unfortunately this node seems to just be attenuated from the center of the attenuation i.e. is a sphere rather than a capsule. Is there a way I can make the ‘Crossfade by distance’ node follow the attenuation shape of the Sound cue?

Thanks in advance.