Pancreatitis is caused by a sick and inflamed pancreas spilling the wrong digestive enzymes in an ill-timed release that starts dissolving the dogs own digestive tract tissues.
After reading extensively in the veterinary literature, it seems to me that dogs fed unnatural amounts of carbohydrates (as in commercial kibble diets) have to produce too much insulin in an attempt to control blood sugar spikes, which is a stress on the pancreas, and also need to produce grossly unnatural amounts of the enzyme Amylase (necessary to digest starches). Both the endocrine (blood sugar regulating) and exocrine (digestive enzymes) functions produce a stressed pancreas due to unnatural amounts of carbohydrates being consumed.
A carb-loaded diet (that is sub-standard in protein and fat) conditions a dog to release large amounts of Amylase in anticipation of meals, because that is what the dog is used to getting (heavy carbs). So when a very heavy fat meal (especially cooked grease) is fed to a dog conditioned to release Amylase, which is the wrong digestive enzymes to digest fat, the pancreatic system goes hay-wire. The fat meal may act as a trigger on a system that sickened, inflamed, and conditioned to a low-fat, low-protein, high-carbohydrate diet, but it isn't "the cause" of the problem.
When dogs are fed a raw diet that is high in protein and fat, the pancreas produces Proteases (the digestive enzymes needed for protein) and Lipases (the digestive enzymes needed for fats) in natural amounts in response to a natural diet. The steady release of energy (blood glycogen) that comes with fat burning does not stress the blood sugar regulating side of the pancreas. And the digestive side is not burdened with producing unnatural amounts of the enzyme Amylase.
With raw fed dogs the diet helps keep the pancreas healthy. Fat is what dogs are supposed to use as their primary energy source. A fat-conditioned dog is very efficient at turning fat into sustained energy. It is healthful for them to get plentiful fats and proteins. It is not healthful to undermine canine health with unnatural amounts of carbohydrates. Dogs require zero carbohydrates according to the National Research Council, the world's leading authority on canine nutrition.