It is good your doctor is going to do an mri of your brain but have you had one of your spine?
I am not sure about the Lyrica dose but sometimes a combo of meds can help too. Can your neuro refer you to a pain doctor? I am not a fan when a doctor just treats all people with a dx the same. Yes we have things in common but we all respond different. My best pain doctor after a few was one who looked at me as an individual and my symptoms,pain,etc.
The orthotics and insurance coverage may depend on your company. Could you call them on Mon? My mom does not have this issue but she has custom orthotics for a problems and they have helped her.