I meant to mention that as well. Damaged moorings are more likely to be caused by people running them over than by lack of maintenance.
I would also agree to not trust the park's service moorings as you would an overnight ball. They clearly do not get as much attention and to be fair are not intended for the same purpose. I'm sure all are aware of the recent issue at the Baths with a park service ball, but the ball also should not have been used given the weather conditions at the time. Use good judgment and be aware of your surroundings and decision making and you will be fine.
ENJOY!! Change is the only constant and things are not the same as they were 10, 20 or 40 years ago, but the BVI are an incredible place with incredible people. You're going to have a great time!
As an aside, doesn't hurt to check your insurance/damage deposit policy with your charter company and confirm whether it covers the dinghy or not. Depending on that answer, you may wish to adjust your risk tolerance and decision making accordingly.