Sorry you are having trouble with this.
USA has had different restrictions/ requirements from Canada in regards to Covid testing for entering Canada/ stopping in Canada on a cruise ship.
The latest requirements are updated on the Princess website: August 15/22.
There is no reason to fret over what was, has been.
I am going on the Canada/ New England cruise.
I am fully VAX, booster, will do a Covid antigen test 2 days prior to embarkation in NYC, and fill in the ArriveCAN app just before I embark.
This is exactly the same as I had to do to board the Discovery Princess May 4/22 in Vancouver.
of course, it will be nice if the testing requirement is dropped by October 29/22.