Ann: Positive Results for Australian Prospective Paediatric Study, page-310

This is my understanding as well, so the whole "people are useless and can't control the environment" argument is kind of moot when the telehealth provider will be able to confirm the quality of the recordings before and after.
And presumably in the event it's not a clear sample, take another one right then and there on the same call, because it's a cough, not a blood test, x-ray or any of the other time consuming and expensive methods...