Hello! I also live in Seattle and am new on this site. I think my OBGYN did a good job diagnosing my endo via surgery and was very helpful in referring me to a specialist for my upcoming surgery. Her name is Dr.Oman and she has an office at the Polyclinic, Seattle.
There's a closed group on Facebook called Nancy's Nook Endometriosis Education. It is very different from this support group because it is more strictly education and research based but they have a list of surgeons based on location that they've found based on certain criteria and have been deemed endo surgery specialists, if you havent already I would give that a try and see if anyone on there is close to you! Once you find someone from the list you can search them in their search bar and lots of times you can see others reviews and experiences with them!