Hi also American, here 15 years after moving from UK. Had 3 failed ablation surgeries with Hugh O’Connor and went to London for excision surgery in 2018 with Peter Barton Smith. Laya covered the cost as I argued that the expert treatment I needed was not available here.
Waiting to see Hugh D O’Connor to get my expired Mirena removed. My endo was dealt with in London fortunately and pain free after 20 odd years. Worth checking if your insurance will cover you to go elsewhere.