Interesting, I’ve not heard of this shell of ice, and I believe in a young earth. I have heard though of a similar hypothesis based in Genesis 2:5-6 which proposes that it did not rain before Noah’s flood and that plants were kept watered by a heavy mist and/or extremely humid atmosphere. Acoording to this idea, that excess water in the air and ground would’ve been all condensed by God as part of the flood.
I’m not sure I entirely agree with the hypothesis, and I do not believe it is essential biblical knowledge so I don’t concern myself with it, but I have heard it before.
Funnily enough (not funny actually, considering the war crimes and all), the Old Testament says that the Jews/Isrealites will never get rid of other people living in the area due to not driving them out in their original conquest.