Don't worry about mooring balls. The grenadines are very easy to anchor
in and you can even snorkel down to see your anchor if you want. Much easier than up here in the PNW.
I would ask the charter company about locking the dingy. You can take a long bike security cable and padlock with you if you want. It doesn't need to be Stainless steel
for a 2 week trip.
Beware that once you leave Grenada for the Grenadines, the short open water
stretch between can blow real hard at times, so be prepared to reef.
Entering the Tobago Cays there are a lot of coral
heads, go slow and have someone on the bow.
Anyone remember where they have to check in at...? Union island?