I refered 2 months ago I know they did their daily goals the first month, but not sure about last month or this month.When did you refer them? It actually takes some time to credit. I believe the person you refer has to earn a certain amount of SB (300 I think) before you collect your bonus.
The one thing AmEx is bad on is describing what you can use them for, but since they process like AmEx I'd think you could use them to make payment on the cruise at least and most likely could use them onboard. 