I have only fellow fan sites to rely on right now, but all signs point to yes...both are open. I believe Tangaroa Terrace is indeed a quick service location, so no ressies required. I'm not sure about Trader Sam's though. I think it is strictly a bar (though it appears the bar and restaurant share patio seating, so you could probably grab some food and have a drink) and I'm not sure if they will have a reservation system in place there.
If you happen to find out, could you please let us know? We plan on checking it out in August and we're figuring it's gonna be crowded. If ressies might be needed for the bar, we'll make them ahead of time for sure! Thanks!
(Hey Wizz, sounds like a new place to check out for one of your "liquid lunch meetings"