My thoughts were that some members have found their bite improved after ES surgery, so maybe that should be tried first, BUT having read your explanation above about how you believe the jaw surgery will be necessary anyway, and also if Dr Osborne is encouraging you to hold off on the styloidectomy then maybe you should take his advice?
@vcp02 posted some interesting info about her appointment and treatment with an integrative dentist, and how the bite and jaw can affect the neck, so maybe with the treatment you’re having will help with your ES symptoms? Here’s a link: