They may need to talk to your pain guy anyway. Most insurance companies WILL budge if they are given docymented proof (your chart) that what they will pay for will not work. Had to do the same with my husband's stomach meds-called many docs from way back when my insurance changed and they suggestion OTC Pepcid-uh, hello, like we hadn't already thought of that! The doc can also help by getting "pre-approval" and pushing it through the system. However, he will also be on the phone going through the same elevator music, so if he agrees, send him a card-you know what he had to go through.
Hope that helps
Lori Lee