The Radisson shuttle will work for you, too.
Avis is on the hotel property just next to the main entrance.
You get the shuttles at the same place, which is the main parking lot across the road from the ship terminal. Just jump into whichever shuttle is more convenient. The Radisson shuttle took our entire party of 5 and another party of 3. The luggage porter helped us with our bags all the way to the shuttle and helped load them onto the van.