I only use the site thru the cruise line. Never have I used an "outside" source. Not that gutsy I guess.
Dunno about what the RCCL lady told you but when you book thru the ship you are somewhat protected by the cruise line if your excursion runs late etc. They know you are there and won't leave you behind.
I don't feel like we've ever been ripped off by booking thru the ship, just a piece of mind that we'll be fine and have a GREAT time
Kerry, you will be fine and sounds like you are in for quite an adventure!
2005 Carnival Spirit to Alaska
2007 Carnival Conquest to Western Caribbean
2008 Royal Caribbean Explorer of the Seas to New England/Canada
2010 Royal Caribbean Explorer of the Seas to Southern Caribbean