That's the impression that I got when I tried to collate known survivor accounts with the final events. I discussed this with one of the authors of OASOG but he felt that was how it most likely happened.
Another point that I was (and still am) unconvinced is the degree of righting of the port list in the final 2 minutes or so. I accept that the port list reduced by a couple of degrees just before the final plunge, but I find it had to believe that the ship came back on "an almost even keel".
They probably thought it was the most reasonable cause of the “rising deck” that occupants on the port side noticed.
In my opinion, I think this animation was one of the few to portray how long the stern sat horizontally and near vertically. Apparently there was some discussion in the boats that the stern might float after all! I think the amount of time they set it to allows for this kind of impression for someone in a lifeboat.