I’m no scientist or biblical scholar either. But it seems to me all the arguments make some assumptions that are usually unspoken. The major one has to do with time. There is an assumption that the flood happened a few thousand years ago, whatever it might have been, and that it occurred within those conditions we understand prevailed then. We don’t know that. We are assured nowadays that the human race is perhaps 200,000 years old, up from earlier guesstimates. But we don’t actually know that it isn’t a lot older than that. We don’t know what the conditions of the world were at the time. To get really far out, we don’t even know that it happened on this planet.
I don’t doubt there are scientific thinkers who have arguments that it had to be X number of years or none. But then, scientists in the 19th Century criticized the creation story because light couldn’t have predated the sun. Of course, we now know that it not only could, but did. We also know creation of the universe we know was sudden, but took billions of years to reformulate itself to what we now see. The creation story doesn’t tell us what a “day” was always, and certainly not before the existence of time.
But it’s the nature of humans to question things, so I’ll not belabor it any further.