I would imagine after 5 years it's a tad late for any treatment. I read up on this stuff a year ago and as far as I can recall Bells Palsy aswell as RAMSEY HUNT SYNDROME is something where treatment should be started ASAP as I believe there is a limited time for improvement 3-6 Months?.
Providing you didn't suffer suffer any vertigo type symptoms, sickness, nausea, soreness inside the ear at the time this all started, we can count RH Syndrome out as this condition is often confused with Bells Palsy - the only factor they typically share is the drooping of the face and sometimes an upper eyelid, apart from that they are very different. RHS is part of the Herpes Zoster virus (a form of shingles!)
Some facial excercising may bring some improvement