A flight at 12:30 out of Vancouver after a cruise was already pushing the limit on making the flight; now ......
Suggest you might want to look at a later flight or overnighting in Vancouver and catching an early morning flight.
Abkhazi Gardens gets my vote, do make a reservation (this applies to any of them).
Actually any of the ones Martincath win over the Empress for all the reasons they stated.
I highly suspect that the cruise line is going to be asking for this letter before you set foot on the ship.
Get it notarized and as previously stated, get a medical authorization letter too.