Blowing stern of on purpose in this case is scutling mate. You better get your terminology right ! :p
Why is this so hard for you. You not willing to admit that the USN could not even sink a target that is sitting still ?
Also: In WWII it was common practise (if possible) for merchants to beach their boat when they had a hole in the hull. This would make it much more easier to repair the vessel and safe it. According to you those should be listed as sinkings too. But dang, they never sunk, ah, who cares, we still call it sinkings
But I guess you are right about the O 19, she sunk, that is why 10 years later she was still on the reef sticking out of the water during high and low tide.