Patience and hope
I had Miller-Fisher. For me, Hope was the kicker. Let your patients know that the odds are way in their favor that they will recover and that the chances of relapse are slim. Statistics support this.
Therapists used electrical stimulation on my face but I do not know what value it had. For stimulation, I used a frozen bag of peas, 15 minutes each side several times a day. I used a tool that was designed to pry the mouth open a little at a time but I found it to be useless. From my experience I believe it just has to take its course. I do know that after I could see and was able to care for myself, progress accelerated.