We had a great time with Viator. Our trip began with a ferry ride from the Port of Brisbane, for which we had to pay an additional $70, including national park fees (as mentioned in their description), along with on-site parking of $20 (which is available if you arrive early - we arrived 30 minutes early). The advertised time for catching the ferry at Port of Brisbane was 7:30 AM, but after booking, the confirmation email stated the time to be 9:45 AM, for which we received multiple reminders as well.
We started our day with lunch. They provided wraps with both vegetarian and non-vegetarian filling options, which we could fill ourselves. Our first activity was kayaking, which was a bit challenging for us as we were new to it. Navigating a kayak with strong waves, wrecks, snorkelers, and other kayaking people from another group was not easy.
The next activity was snorkelling, which was fun. They provided us with a wetsuit, snorkelling gear, and a life jacket. Being a non-swimmer, it was challenging at first, but as I got into the process, it became enjoyable.
Our third activity was sandboarding, for which we had to catch a 4WD bus. We had very little time to change our clothes, use the toilets, etc. It started drizzling as we reached the dunes, and there were no toilets at the sand-boarding spot. As it drizzled, the sand became wet. They gave us wooden boards, which were getting stuck in the sand and were not slipping over the sand (probably due to the wet sand). They also had a very limited number of plastic boards, and we were taking turns using them. It would be great if they could replace the wooden boards with the plastic ones.
Overall, the experience was good, since we did all of these activities for the first time. We would recommend it to others.