@edgarblythe,
The overall conclusion (even though one historian , who was using an argument of sabotage, to load in her book), was that the overloading of the boat (only 300 people were supposed to be on, not 3000), the inclement weather and the overloading caused the boat to be unstable and top heavy. ALSO, the Memphis Quartermaster a "light colonel Hatch" (who had a really spotty history of taking bribes, being brought up on charges, and earlier removed from the position) was clearly loading up the SUltana because he had a "deal" with the SULTANAs captain to maximize his revenue (the boat capts were paid 10$ for each prisoner
carried home)
There were at least 3 other Union steamer boats who could have divvied up the passenger load but were dismissed without any passengers.
Colonel Hatch was interceded for by his brother, the Illinois Sec of State. His brother was tight with LINCOLN, who ordered Henry Halleck to dismiss any potential charges against Hatch (just before the sinking). AND Hatch was promoted to Full Colonel, based totally on patronage.
After the fire and sinking, Hatch ignored 2 subpoens and just kipped over any charges. The loss of life was about 2800 people and , compred to the total loss of life of the War, and the death of Lincoln, the entire matter was pretty much just a matter of record rather than any action or discipline.
The sabotage story had many fans but the "coal bomber" (forgot his name), was only brought up as a possibility by a newpaper reporter who did a "cold case" story 22 years after the incident.
Mot of the steam pilot and engineers and the Sultana memorial Committee, all are convinced that the boiler burst because of a steam explosion rather than a bomb. The forensics that supported that conclusion was mostly from the pattern of the boiler explosion. It occurred above decks and the ship burnt and floated along to the water line. Had it been a bomb (forensics said) the explosion would have blown both below decks and above decks and the ship would have sunk due to the hole blown into its hull.
They went over each of these items and how the "experts" arrived at each point.
Colonel Hatch was left holding the bag. Ill bet his descendants are real proud