Dear Jaybay, I am sorry to hear of your loss.
First let me say that I am obviously not a human gastroenterologist so my knowledge of ERCP and stents is very limited, however I do believe that ERCP and Stent placement is not commonly performed in dogs even today except on an experimental basis. It sounds as if your dog had such a serious pancreatitis that she may not have survived ERCP and stent placement even if it could have been performed since it requires anesthesia.
I believe that, "(ERCP) Endoscopic retrograde cholangio-pancreatography" is a combination of procedures (endoscopy and fluoroscopy), which are used to investigate bile and pancreatic ducts and their surrounding tissues for abnormalities and for patency (open-ness), size, and function etc. Stents are placed in these vessels during the ERCP procedure.
The procedure is performed in humans. Stents are flexible, non-toxic tubes that are placed in vessels to help them hold their shape so that the vessel does not close, collapse, or telescope, etc. Endoscopy is a procedure in which a long camera tube is inserted into the abdomen through an incision or down the esophagus and fluoroscopy is when dye is injected into vessels to better illuminate said vessels for a moving X-Ray diagnosis. The ERCP procedure is used for radiographic imaging of the biliary and pancreatic ducts to help in diagnosis of pancreas and gall bladder abnormalities, and to place stents.
Lastly, You are correct in that high amounts of fat are dangerous to all dogs, but even more dangerous in females and obese dogs.