OMgoodness! I would have had cardiac arrest if my kids did that! Yikes. We also gave them the prepaid cards and when they were gone, they were gone. Gave them something to do instead of grumbling when I wanted to do something for the little ones.
We have enjoyed Ohana's both times we've gone but I think it may be that our reservations are always for non peak times, we've had excellent service, they are always willing to bring my picking eaters (toddlers and teens) something else if they don't like the items on the buffet and I don't know what I'm missing from the "old menu"
And to add to that, our one and only meal at Konas, was at a crowded time, we had horrendous service, food was cold (breakfast, cold eggs and french toast are just yuk)and they messed up our bill! But even with all that, I'd try it again just b/c it does get such good reviews normally!
Final note, if you stay at the GF, can I come too? It is the one place I would love to stay at as well and with our 4 little monsters it won't be happening on my ticket anytime soon!
Have great trip! Let us know how it goes.