Hi,
You cant see wishes from Kona Cafe. If you are planning on eating and going outside to see the fireworks, I would make an ADR for approx 1.5 hrs before wishes. That should give you plenty of time to eat and then go outside to see the fireworks from the beach (watch out for those biting sand bugs!).
If you want to see wishes while you eat, you may want to go to Ohanas. We usually make an ADR for approx 1 hr before wishes is going to happen. We havent missed wishes yet using this timeframe. If they are a little late getting you in, you will still be ok. Also, ask them if you can have a table by the windows to see the fireworks, they usually try to accomodate.
HTH........
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