I've searched the thread for the word "technical" in one of your posts. The only "JAIC technical report" you have referred to is "its part-report, 1995, which was a technical report". The only report I've found corresponding to this is the April 1995 JAIC "PART-REPORT covering the technical issues on the capsizing...", but this doesn't say anything about the ship floating on a 90° list, it says, at section 1.3, that the ship listed to over 90° and sank. You say that Bjorkman cites sections "1.12.5, 2.16 and 5.5", but the part-report doesn't include these section numbers. Are you referring to a different "part-report, 1995, which was a technical report"? If so, please provide a proper citation, and preferably a link, to the report you mean.
The JAIC final report, by the way, also says nothing about the ship "floating on a 90° list". It reports the ship listing to somewhere over 90° and then sinking. See section 13.2.6 and figure 13.3.
The mere fact that the ship didn't sink within 35" of reaching a 90° list doesn't mean that it "floated on a 90° list".