You are now in a quandry involved with Doctor #3, who wants to do a blood test which may or may not pick up elevated enzymes, and is worried about kidney function.

What I would do if I were you would be to tell Doctor #3 to talk to which ever Doctor made the original diagnosis of chronic pancreatitis and let them justify to her their diagnosis. Remind this Vet that another Vet has indicated Xrays show the pancreas as swollen. Given your financial condition ask this Vet her advice for a low fiber, low fat, low salt diet to be tried for a week. If you believe the current pain medication isn't working then ask for Demerol or Torbutrol- the later also have some muscle relaxant properties. Assuming the dog is able to deficate once a day on this diet, and if things are not getting better then ask the Vet if rather than a blood panel, possibly an ultrasound of the rear body and body cavity might not be a better use of your funds. The idea being to see if there are any physical causes such as cancer causing the dog problems when deficating?

For either condition a high fiber diet should help. You're sort of in a work around mode, where you have to hope the pancreatitis (if that is what is involved) won't get any worse, and will resolve itself as before. Also try to eliminate other causes such as cancer causing problems.

P.S. I'm still amazed a Vet would soak you $200 for what amounted to be an ear cleaning.