Yes, that is it. there are 3 images in historical images that go back to 2006 on Google Earth. Does that not look like a sub or U-boat? it's slightly on it's side. You can look at it from different angles. It is a known wreck, just unidentified. The bow area looks caved in like from depth charges, also you can see the rectangular holes for I'm guessing blowing the ballast. (I obviously know little of subs or nautical terms). I enjoyed your Geology report. I am a retired Geologist, and understand French enough to get most of it. The wreck might not be mentioned, possibly it wasn't there yet. The report was done in 1979. If you look at South Equatorial current and the Mozambique Current I could see the wreck being swept there, possibly trapped in the layer between the deep cold and the warmer top water and slowly drifted deep there over the years. If I was rich, I love to go dive it...but I am not . It looks incredibly beautiful there. I live in Oregon, USA. Lots of trees, which is good too.
Patty