Our organization issue the Iridium Extreme when we need to be at locations without cell service and need to get in touch. We are talking about post major disaster relief in rural areas.

Many cruise terminals worldwide has calling cards that you can buy with phones nearby to use them. Much lower cost solution.

Ship to shore is expensive but in our experience there is discount or complimentary in case of emergency. RC cruise which my parents were on was expected in port the day after the famous earthquake in Santiago. The ship was unable to dock and was at sea for one more day. The airport was closed postquake for 4 days after. The ship gave each room a three minute ship to shore call so the passenger can inform their family that they are OK and I, as a Fter informed my parents of their new flights and insurance covered accommodations and food allowance that I remotely arranged for them. (thanks to wisdom learned here)