I definitely think that could be the case (catastrophe/flood). There's quite a bit of evidence supporting some kind of catastrophic "mud flood" scenario, but it's hard to pinpoint the timeframe or how widespread it was. I'm just having a hard time imagining a scenario where such a large landmass could move it so much in such a short period of time. It seems more likely that they just made up map details, cartographer sitting in his quarters the whole time with free license to invent an entire place so that they can go get some Mayan punini and get paid when they get home.