Glad the LP looks clear at least - would have expected that it should be - by clear I assume no WBC.. Her CSF Protein might be elevated some which might point towards the viral.. might have some lymphs too
Make sure he send all the viral titers (enterovirus, arbovirus, west nile, eastern/western/st louis.. could send Lyme for kicks).. AFB, etc
I don't have the whole history but I'm sure someone's thought about autoimmune/rheum things (lupus, sarcoid, wegener's, on and on...) - some simple ANA/ESR/CRP/ANCA/ACE etc should rule those out.. if there's any inflammation/etc the ESR/CRP will help too..
I wouldn't "assume" anything as well (no disrespect intended), she may need a HIV Ab/HIV viral load, RPR, etc.. He can send Mycoplasma titers, Mono, etc
Are you around any cows, animals, chickens, birds, etc?
Keep us updated