sorry to hear your story.
please indicate specific questions you have because I can write a textbook to explain your case.
no one will do exploratory craniotomy....
palatal myolconus is a very specific condition and as far as i remember there is only several conditions where it is present - one of the most common is stroke or other pathology affecting brainstem, yet it should not cause CSF leak, but may be responsible for those muscle twitching you were referring to. Previously described chemical meningitis with scarring of the dura around the pons may put "tension" on those fine neurological structures and produce SOME of your symptoms.
in reference to muscle atrophy and deconditioning - need to figure out if it is pure deconditioning versus motor neuron disease - EMG may shed some light on it (whoever does it - make sure they are neuromuscular specialists and they do tongue emg as well).
If for one second we disregard the CSF leak possibility - meningitis with secondary scarring and adhesions would explain majority of your symptoms.
If SCF leak is dominant - one would expect postural headaches. I have a patient with CSF leak for over 30 years (post pituitary surgery) - he is in his 80s and functions very well (it all depends if amount of leakage is more than amount you produce) and postural headache differentiates between them.
Upright MRI will only show meningeal enhancement (false positive if you do it close to LP/myelogram date) wait a little longer... unfortunately, it will enhance meninges diffusely - still will no idea where the leak comes from.