We were on the Zenith last month..............We didn['t do the tours you were asking about........
Have read that a lot of people are having concerns about being safe in Costa Rica after the recent problem a cruise tour had with muggers.
We hired a private tour guide in Puerto Limon and had a group of 11 people from the boards. Eduardo Humphrey was our personal guide and he also had a driver- both of them never left our side. We stopped at the local supermarket on our way back to the ship and they even accompanied us into the market to make certain everything was OK!
If you want to feel safe with a local guide who gives an excellent tour give him a try , he was great and very inexpensive - we paid $45pp for the all day tour. We did a Canal boat tour of Tortuguero (tour boat has a covered top), went to the Del Monte banana plantation and also visited the National Park of Cahuita, with its white sand beaches. He has other tours available too, we selected what our group wanted to so.
If you have any other questions you can email me at firstname.lastname@example.org
You will love Costa Rica!