Hi Pam @pamclark, I have no experience with cough syncope but do agree with suggestions from @lisalucier and @dawn_giacabazi. I'm not sure if it's an option for you but Mayo Clinic is very good at diagnosing difficult and rare conditions. If you would like to seek help from Mayo Clinic, you can contact one of their appointment offices. The contact information for Minnesota, Arizona and Florida can be found here:
https://www.mayoclinic.org/appointments
I did find some references which may be helpful understanding the condition.

NIH - Diagnosis and treatment of syncope
-- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1861366/

RepiratoryMedicine - Cough Syncopy
-- https://www.resmedjournal.com/article/S0954-6111(13)00435-6/fulltext

I think recording the episodes and keeping a log until you get help is a good idea. I think this will help the doctors/specialists diagnose the cause and come up with a treatment. Hoping you find some answers soon.

John