Ok, I’ll let the secret out - it was full of torpedos for an invasion of Canada and one of them accidentally detonated.
No, that’s not it. I didn’t watch the vid, but as I recollect it, this ship succumbed to the waves. It set out late in the season when most shipping had already stopped.
Wave height depends on wind, and in the SW to NE direction along Lake Superior, there’s a hell of a lot of runway for wind to develop.
Big waves, fully loaded ship.
No mystery, just tragedy.
They for got to disarm the depth charges, and one broke lose in the storm, went over the side, then detonated, rupturing the hull?
I’m not saying it was aliens...