For sure -- ACTUAL liver failure can kill you within a day or two if left untreated. As morbidly hilarious as it'd be if Caden was live-Telegramming his painful demise from cirrhosis with sad furry stickers, he's full of shit as per usual (ba dum tss).
I'm inclined to believe that there is actually some sort of issue with his liver, however, just because it seems an oddly specific thing to lie about. Presumably this is a similar situation to the time he got beat up a few months ago, where there's most likely an element of truth to what he's saying, but it's been stretched beyond plausibility out of a desire for sympathy/engagement. That seems to be a common theme with him.