I saw a doc on Youtube (sorry can't remember what it was called) about the German invasion of Norway and that was the gun that sank the Blucher. So you are correct.The are pics below are from the Warfare History Network website.
Great articles and excellent pictures.
I print the articles to pdf’s and read them at my leisure.
This before and after is from “Assault on Oslo: The Naval Disaster in the Drøbak Strait”
It doesn't say so but it sure looks to be the same gun.