A 66-year-old patient presented with bilateral nearly-flaccid facial paralysis (no synkinesis). Fourteen months ago following a sinus infection they had a tissue biopsy (? Mucor because he has chronic lymphocytic leukemia, but negative) and extraction of an impacted molar.

A few days later they developed left-sided facial numbness with overlying cellulitis. They were given IV antibiotics but began to develop left facial weakness, and by the following week also developed right facial paralysis.

They had a massive workup including multiple MRI scans, lumbar punctures, and other hematologic workup – all unrevealing but MRI first showed masseter myositis which was then resolved on a follow up scan. Other cranial nerve exams normal. There was trace recovery on the right, completely flaccid on left, now 14 months in. Two months ago he lost all of his hair, possibly due to autoimmune alopecia, now on IVIG.

What do you think the diagnosis could be?
What would you suggest as management?