You guys sure are missing the part about the OP not being into the whole alcohol scene. Ha
I was stuck in Icn for about the same amount of time. The KE lounge was ok. There is a nice “quiet” section that had super comfy chairs. Can’t say much about vegan options since I don’t swing that way. Had some nice selections of tea though. Reserve a shower about 1.5 hrs or so before your flight. Nice shower room and really perks you up.