Hi, Andrew. Welcome.
My first thought when you mentioned a salt craving was Addison's disease. And a neurologist is not the one you should see for that but an endocrinologist. I highly suggest that you do see one as soon as you can. Do you have unusual sweating? Loss of weight? Feeling more tired towards the end of the day when cortisol is at its lowest? A good endo will do morning, fasting labs (especially cortisol and other tests like ACTH). If you have Addison's, it's nothing to mess around with.
Have you had your B12, vitamin d, thyroid and CBC done? Your primary doctor can do that. A B12 deficiency is common, especially at your age, often goes undiagnosed and can cause a lot of neurological problems, especially peripheral neuropathy.
I would also suggest that you get copies of everything that the neuro did do, such as the EMG and the blood tests. Always get copies of your records, which they should give you free of charge. And you have the right to know exactly what those test results mean, which it doesn't sound like you do. Sometimes doctors run tests and they "think" that's the logical end of doctoring. It's only the beginning.
Can you describe in what muscles you are experiencing the weakness? MG often begins in the head/neck region, with ptosis (toe-sis) being the first sign of it. Ptosis is eyelid drooping but it can also be eyebrow and face drooping!

If you do notice you have ptosis, take a photo of it.
Yes, MG is all about fatigable weakness. It's unique in that way. Is your weakness confined to the bulbar muscles? Since MG starts in those areas, it should be considered in the differential diagnosis.
So you might need to see an endocrinologist and your primary doctor as soon as you can to "help" the neurologist in figuring all of this out. And don't assume there's only one thing going on. There might be more than one.
I hope you'll get help soon. Please holler if you need more help!
Annie