The risk I see is, if there is another requirement in the future...

The risk I see is, if there is another requirement in the future for US clinical studies, which means putting the app to the test in a US environment. If the US study conflicts with AUS and current studies, then it might even appear like RAP did, which I consider unlikely given we are already in market with Aus and starting UK, and there have been additional positive feedback from real users on the efficacy of the app. Or alternatively if the clinical data is bogus to a degree, or the credentials of the people who ran the study were dodgy, See NTI - mente autismn about that.

If there is no need for further US clinical studies, then based on current studies completed already and the fact this is obtained for Aus and CE Mark European Clearance, then I believe the studies results are at a standard that the expectation of an FDA failure is actually very minimal. In addition to how the US have actuallly created the De Novo pathway to get more low to medium risk devices through quicker

"The US Food and Drug Administration (FDA) has been steadily increasing the annual number of granted de novo classification requests in recent years and hit a record of 44 de novos granted during 2018.

The de novo premarket review pathway, used for novel, low-to-moderate-risk devices that are not substantially equivalent to already marketed devices, has increasingly attracted interest in the medical device ecosystem, particularly after the quick turnaround for Apple’s granted de novo classification requests last September."

https://www.raps.org/news-and-articles/news-articles/2019/4/fdas-de-novo-program-gains-momentum