Both restaurants are great IMO ... we did WCC for "late lunch" - around 2:30 if I remember - on our MVMCP day. (We intended to head straight to MK using the boat from WL but for some reason, we ended up actually going back to ASMu before heading to MK ... but still got there way before the official start of MVMCP).
Not sure how this impacts you or not, but the food at WCC is more "standard North American fare" while the bbq at Ohanas is different - flavours and such. Ahhh, how to say this tactfully, if you have a sensitive stomach - especially when trying new foods, you may want to save Ohanna's for a night when you haven't paid for a special event.