Sorry to hear you are having a bit of a go with some of your healthcare providers. It's not uncommon for many of us Dysautonomia folks to pedal thru Doctors until we find one that we are comfortable with of helps with what bothers us.
Personally i would not consider a neurologist unless you really think there is a need for one. I have read many folks experience has not gone well and is just one more trip down a empty rabbit hole.
I would agree that seeing a electrophysiologist for an opinion would be a worthwhile effort seeing you have inappropriate sinus tachycardia. Unfortunately there is no magic one pill that fixes this for all.
I was lucky in my search for a good Cardiologist (have fired a number of them over the years) that does recognize autonomic dysfunctions as being valid and has been very helpful.
He will tell you outright from a cardiology perspective that heart rate in the mid 90's or just short of 100 is not killing you but does agree it can be bothersome especially if i feel symptoms like a bit of lightheadedness or in my case feeling the palpitations. We did change out my meds completely to help with the palpitations which did not include Corlanor.
Currents meds are Cardivadiol, amlodipine and ranolazine and this works for me. My heart rate is elevated most of the time from mid 80's to 90's but the Doc is very conservative not to throw the kitchen sink at the rates as we know it will just cause me more issues.
Either way for you it's not out of the question to trial other meds to see you one works better for you. Rumour is that Ivabradine is effective with controlling the heart rates.