The best story I’ve heard recently is that the Titanic was switched with the Olympic (a sister ship which had been badly damaged in a collision with a British warship) and deliberately sunk in an insurance scam. The California was supposed to be positioned to quickly pick up the passengers before the Titanic went down, but that last bit didn’t work out too well.
This has been thoroughly discredited, along with the 'coal fire' theory. Been studying Titanic since the early Seventies and spend time on line now with folks who were involved in her discovery and have been down to the wreck and nothing will make them say 'not this s**t again' faster than this. :-)