When we sailed from USVI to Culebra we had 2 UK citizens on board with ESTA. We used CBRoam but had to visit the airport in Culebra to clear in the 2 Uk citizens. I think it all depends on who at US customs reviews the application.

On a more recent trip into Cruz Bay our CBroam application (with 2 UK. Citizens ) was denied !! We visited the Cruz Bay office …had to fill in a new app for the US Citizens, UK citizens processed separately.
I asked why the denial … basically the answer was it depends on the customs officer reviewing the application.

I prefer checking out of BVI at West end or Josh, Less likely to get caught up in ferry traffic.

Bob