There is no way to say if she will survive or not or how long she will live. Not even her doctors who know all about her condition and sees the test results and are educated on her condition is able to do that. Stage 4 just means she has at least some cirrhosis. This staging does not detail how much scar tissue (cirrhosis) your aunt has. It could be very little to a lot which makes a huge difference in how fast she would reach total liver failure. There was really nothing your aunt could probably do about 2 years ago since there is no cure and all the doctors can basically do is treat the symptoms of the disease as it progresses. Nothing probably would have changed just because she did nothing in those 2 years. The disease does what it wants to do unless your aunt can slow it down or stop the progression in some way such as an alcoholic can stop drinking and help it. There is no cure for it other than a liver transplant.
If she is still on the list even though she has cancer, that will place her higher up on the list for her transplant. Yes, your aunt does have to find a matching liver, but a liver is not as hard as some other transplants to find a match. All she needs is someone with a compatible blood type and be similar in body size. They don't want to transplant a huge man's liver into a tiny petite woman since it would just be too big. It's just a wait and see situation as to what happens with her. I waited on a transplant for myself which was an 18 month wait. They base that listing on what is called a MELD (model for end stage liver disease) score which is the results of several blood tests that show how sick the person is and how close to total liver failure they are at the time. It goes up to 40 with 40 being the sickest. That means that even though a person may have been waiting for years on the list with a score of 12, if a person gets accepted and was only on the list for a week and their score was 25, they would get their transplant ahead of the 12 even though the 12 has been waiting for years. I was called for my transplant when my score was 15, but that varies from day to day depending on the transplant center and how many organs they get in versus the people on the list and their scores. It constantly changes.
I don't know if your aunt's transplant center does it or not, but there is thing called living donor liver transplants in which a living person can donate a portion of their liver to your aunt and she won't have to wait on the list anymore. If anyone in your family would be very healthy and willing to donate, that might be an option to help her and save her life. This would have to be discussed with your aunt and her doctors at the transplant center. I hope your aunt is able to get her transplant very soon. With cancer being there, it's critical she gets help before it spreads anywhere. Once it spreads, they will no longer do a transplant most of the time since it will not help.
I'm a nurse who had cirrhosis and received a liver transplant.