Vacation disaster: what should we do? (story inside)Need transport from Ft. Lauderdale or Miami to Bahamas.

It's my grandparents 50th wedding anniversary. This has been planned for years and a lot of money has been spent to make this happen. We were just taking a simple cruise from Jacksonville to the Bahamas, but 41 of my family members are going and my grand parents are renewing their vows. Money isn't so much the issue as much as the sentimental value.

So here's what happened: We arrived at Newark airport 2 1/2 hours before our flight, we were booked through United. Lines were outrageous because of the weather delays the night before. They had zero assitance expediting the process and were extremely understaffed, we ran to United front desk and the finally pulled us out of line, got our bags checked, and went through security. I ran to the gate and 15min before our departure. People were still boarding at this time. I approached the desk and the attendant told me flight was closed and told me to stand in the hour long customer service line. I pleaded, explaining we have to catch a cruise in JAX by 4, and that we had already CHECKED IN to the flight on line. He wouldn't let us on, but another four people right in front of us on. We were placed on standby but nothing opened up for the next flight.
Well, my familys devasted, I'm with my Mom, my sister, two brothers, my aunt and uncle, and their son. My Mom and Aunt have been crying all day.

Our next plan is to try and catch the cruise ship at one of the ports in the Bahamas.

A big obstacle is that me, my mom, sister, and brothers do not have passports to fly direct to Nassau. We got our flight changed to Ft. Lauderdale and I found a ferry from Ft. Lauderdale to Freeport, and booked a flight from Freeport to Nassau (passports are not required for intraisland flight) I was under the impression that a State ID and birth certificate would be enough to ride the because several day cruises do not require it, however, this ferry requires a passport.

Anyway, long and short, does anyone know ANYWAY to get to Freeport from Miami or Ft. Lauderdale, I'm literally talking anymeans possible. We have documentation of our boarding passes to leave the island and our flight boarding passes from Freeport to Nassau to prove we're leaving the island.

This is a last ditch effort, any help is so appreciated, Thanks Reddit