I'm so sorry that you are having such a tough time at the moment. Its seems we all have to jump through hoops to get a diagnosis.

I saw a professor at Oxford who understands that you can hae seronegative MG and a normal EMG. If you would like more info private message me. He is considered to be a world leading expert (even so he still has serious limitations) but he has developed alongside Angela Vincent a new more sensitive blood test which picks up antibodies that a standard test does not. It maybe a possibility worth exploring.

I hope this helps

Love
Rach