It's worth noting that Karahan Tepe, Gobekli Tepe, and most of the other PPN-A/B sites in Southern Anatolia are on top of hills and mountains at fairly high elevations. They're not really candidates for any sort of flood event.
As for the poetic feel, the term of art is a 'just-so story'.
Just for wonder's sake. Do you think it could be possible for a system of underground waterways to basically be pushed uphill by a natural dam breaking and the pressure of the Mediterranean sea forcing the water to sort of gush uphill?
> "In the Estonian village of Tuhala, there is a well that starts spouting water after a heavy downpour. The well happens to be placed just over an underground river. After rain water floods the river, water pressure builds to the point that it shoots up out of the well, sometimes up to half a meter high. This continues for a few days. During this time, more than 100 liters of water can flow out every second."
Kipling has a book of "just so" stories that I enjoyed as a child. I'm sure I'd find most of it more cringe as an adult. I think you're correct though that it fits the poster's usage.
As for the poetic feel, the term of art is a 'just-so story'.