Hi CurleySue,
I'm in a similar position but its my policy and my husband is the named driver, he was in an accident over a year ago and hasn't driven since. Like your story when my insurance came up for renewal I asked to take him off my policy as I figured I would save money ... yeah right, turned out it was cheaper to keep him on it. In our case both of our insurances were with the same company so they were well aware of his accident (he was in the middle of a claim as he was hit by a stolen car), they had no problem keeping him on as a named driver, the only thing they flagged for him was that he has two years in which to reinstate his own policy or he will lose his no claims discount.
Funnily they never asked about him being medically cleared to drive or looked for information regarding him not being cleared to drive. He's back with the consultant next week so must get him to check (although I think the bigger problem will be getting his head back in driving mode)