Yes, this sounds like a rare condition, and really only your doc could advise you properly. If he doesn't have answers for you, how is your liver holding up through testing? If you've been vaping a while and your liver function tests are either improving after quitting smoking, or stay the same, I'd say that in your case vaping would probably be as safe as smoking, but not vaping at all may be safer. Maybe you can do some testing closer together if you are concerned?
Vaping is a harm reduction device, and it's not for everyone. With that kind of condition, I think I would be wary too. I just don't know enough about it to really give you an informed answer, other than if YOU decide to continue vaping, step up any testing done to see how stable your illness is, and monitor it closely for a while. I have no idea what role nicotine and other vape ingredients would have on your condition. I would want to say it may be safer than smoking, but I do not know that with ANY degree of certainty.
Best of luck, I'm sorry to hear about your condition.
Anna