In terms of the OPs question, it did not sound like the husband had received a denial letter from the FAA.
In terms of whether having a condition that would normally require an SI if one makes a medical application requires that one not use BasicMed when one has valid prior medical and has not received a denial letter and has a doctor that will approve the application, it sounds to me like this will not finally be decided until the FAA decides to violate someone who has gone the BasicMed route under those conditions and it has been adjudicated. By which I mean worked its way up through the administrative law court to the appellate court. I say that because it seems like an issue where the aeromedical division will have one interpretation and Congress and the courts may have another.
But for the OP, I suppose best to consult an aviation attorney before making a decision about it.
