Check out the type of endoscope your doctor wants to use. They can't be cleaned well enough to prevent antibiotic resistant bacteria surviving and several people ahve been made sick or died.
Check out this article before you go so you can check to be safe:
Those are not what is used for regular endoscopies to look for Celiac disease.
The scopes in the news story are for - "The scopes are used for a procedure called ERCP, or Endoscopic Retrograde Cholangiopancreatography, in which the devices are used with contrast dyes and X-rays to help doctors locate and treat blockages in the bile and pancreatic ducts."
This is NOT for regular endoscopies to diagnose Celiac disease.