I don’t believe there were more than dozens rescued. Those external missiles and other armaments don’t explode gently. The ship listed quickly. And there were no other ships in the immediate area. I don’t know if the Turkish rescue story was true but a report of about that number of rescued shipmen reaching Sevastopol does seem credible.
I am not sure what to believe about survivors either.
However, you are correct.
If there was no attack and a fire caused munitions to blow and the ship to sink;
or if there was an attack which caused munitions to blow and the ship to sink;
The idea that all on board survived is laughable.