I'm not a medical student, just a laymen, but I have some interest and some knowledge, so I'm going to put my two-cents in. I don't know if it's more educated, in fact, it's probably not.
I think it would depend on what kind of pancreatic failure and what kind of liver failure. I mean, can't liver failure go on for a while? Sometimes it's within days, but other times it's over years. But someone with Type 1 Diabetes could die within a few weeks of developing symptoms. However, you could argue that it takes 5-10 years to develop Type 1 Diabetes before symptoms start. And that's just one type of pancreatic failure.
I think you need to ask your teacher to clarify what he/she meant by both failures and why he/she came to that conclusion. Let me know what you find out. Now I'm curious.