Enjoy your cruise. Don't beat yourself up over any tech issues. Everyone will be thrilled with whatever you can post, whether that is a little or a lot. You have been looking forward to this for so long, just soak it all in.
Following along Megan! If the kids are really in to snorkeling and you have enough time for an online purchase, I would recommend some anti fog gel for the snorkel masks. If they are brand new they take a few uses before they don't fog up. Also if you have sunscreen on your face it is more likely to fog the mask up. Safe travels!!