The same thing happened to Sapphire Princess last season; the whale wasn't discovered until the ship was docking in Vancouver. I believe it was determined that the animal was dead when struck by the ship. I hope that is the case this time.
And yet several passengers were very critical of a Princess Captain when he took an evasive action to avoid hitting a whale a couple of months ago. It knocked a few people down but there were no injuries--just some broken dishes and glassware. Seems like the Captains are damned if they do and damned it they don't.