My wife has been diagnosed with MCI for 7+ years and has significant short term memory loss and loss of exutive function (planning and organization, doing multi-step tasks) and has had prominent deja vu for the past several years, describing exactly what you have experienced with your husband. She often asks if I remember seeing a TV show (one that is "live" and not a rerun) and I just tell her I have never seen it. I sometimes tell her she is having deja vu and that I know the feeling is real to her. But it (the deja vu) is very upsetting to her.