I know nothing about the currents in the Puget Sound but they do have a reputation for being strong and fast. In a small boat like a Rhodes 19' you are going to need the current in your favor as much as possible since your top speed is probably around 4 knots.
Is there a tide & pilot manual he can get that has the current charts
for the Puget Sound in it? Here on the east cost I use the "Eldridge Tide & Pilot Manual" to negotiate the currents in the East River around Manhattan Island (NY).
The Bell Harbor marina sounds like a safe bet but be ready to fork over some $$$ for the night.
Getting your boat to it's new harbor by water will be much more fun and instructive then trailering it. Using a trailer could be a solid Plan B though.
Good luck, have fun and be safe.