Fine, maybe it’s not retcon because of no body. But there is LOGIC at play here, okay? Sharks, bleeding = feeding fenzy. It takes you out of the moment when the explanation is somehow a mermaid saved the bleeding man from shark infested waters at the last second. It’s eye roll worthy.
So fine, maybe it’s not retconny cause “no body!” but that doesn’t mean it gets a pass on writing.
Maybe you should take it up with Jane, since she’s still replying to people tonight. I’m actually curious what her response would be.