It seems that storing the file is not just a development aid, because it seems they are still doing it after the fix (according to the report, I don't have any compatible product to try it out...). They just make sure to delete it when it is not needed.

The reason they store the file probably has to do with technical constraints. Maybe the audio API they are using only works with files and not memory buffers, maybe the buffer took too much space, maybe it is a workaround of some kind. We won't know without analyzing their code.