SS doesn't want to spend money on CE's, so if they have all your records, you should probably call and speak with the DDS rep assigned to your case. You can ask if there is something specific you need to have your doctor document.
I wouldn't bother complaining about the CE. There are countless incompetent ones and complaints never help. These are docs willing to work for ultra low fees...

Catra, Have you had a Functional Capacity Evaluation?

Are you using a walker or cane? If yes, was it prescribed by your doc? Inability to ambulate effectively without a walker or two canes Meets a Listing and should be a quick approval. CRPS does not have it's own Listing, so it can require going before a judge for approval unless you meet another Listing.