""it seems unlikely because whale's throats are too small, and the few fish that 'might' swalsperm wa man... i.e. big sharks, would not swallow him whole....and so forth..""

Well, while not intending to take sides on the overall issues, the above not totally (scientifically) accurate on the sperm whales throat size. Additionally, there are some fishes that do have the capacity (throat size) to swallow a whole human. While it is unlikely they would do so (from researchers observations), based on that, I suspect the potential is not totally outside the rhelm of being possible.

""Unlike most species of whale, sperm whales have a relatively large throat which is designed to allow it to consume large prey such as giant squid.While these whales do have large throats that would make it easier to swallow a human most of their hunting takes place several miles below the sea, up to 3,000 ft., which is much deeper than a human is able to swim.""

whale facts