Rubbish. It is literally impossible to make a 'NAL compliant' device because it is hearing test software (an automated tone generator). It is not a device standard. [NUH merely integrates NAL software into it's self-test app.]
If you bothered to read the OTC regulations you will discover the requirements are trivial - some basic safety tests and box labelling. Cheap ANC earbuds are already being re-purposed, getting FDA approval and legally being sold as OTC hearing aids online for around USD200.