I think you meant to say west end of Tortola. Given the route you posted dropping them at West End (aka Sopers hole) is perfect for you. You go right by it on the way to Norman from JVD. They can catch the 10:30 ferry. The dinghy dock is about 50 yards past the ferry dock. Grab any open Mooring and run them in. It will not cost you more then 30 minutes extra enroute to Norman.
Your post suggests you were thinking about dropping them to cab to Roadtown. No need for that. Make sure you don't buy roundtrip tickets.